Tag Archive for: fingerprinting

Confused as to which fingerprinting medium is right for the task at hand? Well, Investigator G. Nome has assembled the ultimate guide for the heroes of your tall tales, and he recommends keeping it within easy reach.

Heroes such as Harry Bosch, Jack Reacher, D.D. Warren, Will Trent, or any of their peers, will never again fret over such details.Actually, the creators of those characters—Michael Connelly, Lisa Gardner, Lee Child, and Karin Slaughter—attended training classes at the Writers’ Police Academy to help their protagonists enhance their crime-solving abilities.

The icing on the cake is that many fingerprinting classes at the Writers’ Police Academy are taught by the pros from Sirchie (formerly Sirchie Fingerprint Laboratories). Sirchie manufactures fingerprinting powders, lifters, and a wide range of evidence testing and collection equipment and, well, the list of Sirchie’s products is practically endless. Other printing sessions are taught by CSI experts.

The Writers’ Police Academy and Sirchie partnered to present the unique event, MurderCon.

Anyway, here’s the scoop on processing prints.

Investigator G. Nome’s Guide to Developing Fingerprints

Before attempting to lift a print from any surface, the savvy investigator will first determine the type of surface to be printed. In addition to surface type and texture (porous, nonporous, etc.), other factors must be considered, such as the presence of foreign matters—dust, dirt, perspiration, blood, oils, grease, and moisture, to name a few.

Lighting is important, including the use of alternate light sources and lasers. The latter two can cause the perspiration and oils in found in some prints to fluoresce, making them easy to see without further developing.

Once investigators have determined the surface type and whether obstacles exist (foreign matter) it’s time to select the proper method and materials needed to properly develop the desired prints(s).

Surface Types

As always, the first order of business is to try and see the prints using only the naked eye. Sometimes they’re quite obvious.

Porous Surfaces – first attempt the naked eye approach. If no prints are obvious, then try fluorescence by laser or alternate light source. If that doesn’t quite work, then it’s time to bring out the big guns, such as…

1. Iodine fuming

2. Ninhydrin

3. DFO (1,8-Diazafluoren-9-one)

To learn about Iodine fuming and Ninhydrin, please click here to read my article “Ninhydrin and Iodine Fuming.

Non-Porous Surfaces – again, try the naked eye. If no prints are obvious, then try fluorescence by laser or alternate light source. If those steps do not produce results, then use the following to develop invisible prints.

1. Cyanoacrylate fuming (SuperGlue)

2. Cyanoacrylate dye

3. Vacuum metal deposition (VMD)

4. Powder

To learn about developing prints using SuoerGlue, please click here to read my article “Cyanocrylate Fuming – Fingerprinting with Superglue”

Still not satisfied with your options? Okay, let’s call in the specialists …

Bloodstained Specimens—Porous Surfaces

1. DFO (1,8-Diazafluoren-9-one)

2. Ninhydrin

3. Powder – amido black

Bloodstained Specimens—Nonporous Surfaces

1. leucocrystal violet (LCV) or amido black

2. Cyanoacrylate fuming (SuperGlue)

3. Cyanoacrylate dye

4. Vacuum metal deposition (VMD)


1. DFO (1,8-Diazafluoren-9-one)

2. Ninhydrin

3. Silver Nitrate

Rubber Gloves—Semiporous

1. Iodine spray reagent

2. Cyanoacrylate fuming

3. Laser or alternate light source

4. Magnetic powder

5. Cyanoacrylate dye

6. Laser or alternate light source

7. Ninhydrin

Tape—Non-adhesive Side

1. Cyanoacrylate fuming

2. Cyanoacrylate dye

3. Vacuum metal deposition (VMD)

4. Powder

Tape—Adhesive Side

1. Sticky-side powder

2. Alternate black powder

3. Ash gray powder

4. Gentian violet

Dark-colored adhesive side of tape

1. Ash gray powder

2. Liqui-Drox

3. Gentian violet

* Should the investigator decide to use Cyanoacrylate fuming, it must be done on the nonadhesive side of tape first, then both sides can be processed with Liqui-Drox.

Photographs—Emulsion Side

1. Iodine spray reagent

2. Cyanoacrylate fuming

3. Cyanoacrylate dye

4. Vacuum metal deposition (VMD)

5. Powder

Photographs—Paper Side—Semiporous

1. Cyanoacrylate fuming

2. Magnetic powder

3. DFO (1,8-Diazafluoren-9-one)

4. Ninhydrin

5. Cyanoacrylate dye

Powder and Other Developer Uses

1. Alternate Black – sticky sides of labels and other tapes.

2. Gentian Violet – adhesive side of various tapes.

3. Sticky-side powder – Duh… This one’s for use on sticky sides of tape.

4. Amido Black (methanol or water based) – prints pressed into bloody surfaces. *water based includes a blood fixative.

5. Cyanoacrylate fuming (SuperGlue) – nonporous surfaces.

6. Cyanoacrylate Florescent Dye – used to enhance prints on non-porous surfaces. Best viewed using alternate light sources.

7. DAB (Diaminobenzidine) – developing prints found in blood. Also useful in this situation are Coomassie Brilliant Blue and Crowle’s Double Stain.

8. DFO (1,8-Diazafluoren-9-One) – porous surfaces; reacts with amino acids in perspiration

*Heating a fingerprint to 40 degrees Celcius forces amino acids to separate from a fingerprint. Add a special chemical to the sample and, with a 99% accuracy, the concentration indicates if the fingerprint belongs to either a male or female. Why? Because females have a different concentration of amino acids than males.

9. Iodine Fuming – porous surfaces containing grease or oils; turns yellowish color/stain

10. Ninhydrin – another product used on porous surfaces. Reacts with amino acids in perspiration.

11. Physical Developer – works on both porous and non-porous surfaces and is especially effective on paper currency.

12. Silver Nitrate – porous surfaces, especially paper. Stains caused by presence of Silver Nitrate cannot be removed. Also, prints developed by Silver Nitrate will totally disappear within a few hours, therefore it is imperative to photograph the prints as soon as they’re visible.

13. Sudan Black – a dye that stains sebaceous perspiration on surfaces contaminated by food items of greasy and oily varieties.

14. Vacuum Metal Deposition – non-porous or semi-porous, such as photographs and magazine pages. Use of VMD causes printed material to become extremely fragile.

15. Liqui-Drox – a fluorescent dye used to develop prints on the adhesive and non-adhesive sides of dark-colored tape.

16. MBD (Fluorescent Dye) – used on various colored surfaces.

17. Safranin O (a florescent dye) – used to enhance prints developed by Cyanoacrylate fuming (SuperGlue). Thenoyl Europium Chelate (Fluorescent Dye) is used to stain those prints. This dye can only be viewed under UV light.

More Graveyard Shift Articles about Fingerprinting





There’s still time to sign up for the 2022 Writers’ Police Academy. Please tell your friends, family, fellow writers. And please share the information to your social media. Thanks!


June 2-5, 2022

Location –  NWTC Public Safety Training Academy

Green Bay. Wi



“He’s running!”

A bag of cocaine is tossed to the ground along with a small handgun. The bad guy takes off, and he’s well prepared for the run—tennis shoes and loose clothing. More importantly, he has a small head start … and he’s younger. Much younger. A kid.

You know, it’s difficult to chase someone, especially while wearing a suit and dress shoes, but that’s the nature of the beast. So detectives don’t complain, they just do it. Sure, they’ll hear the teasing from the uniforms, later … “Who taught you how to run, your grandma?” “Slowest chase I’ve ever seen.” “You got weights tied to your ankles?” “You put your feet on backward this morning?”

However, in spite of the awkward, wingtip-clad feet, the investigator almost always catches the thug, wrestles to get the cuffs on his wrists, and stands him upright for the walk back to the unmarked police car. Then it’s back to the police station for processing, which includes mugshot photos, fingerprinting, and normally the prisoner’s phone call to his wife or girlfriend, or both, mother, attorney, or bail bondsman (sometimes, there’s a list of local bail/bond folks beside the jail/police department lockup phone).

The actual foot chase …

Yes, that’s me in the above photo, with sweaty hair pulled behind my ears. At the time, I was working a special assignment where a bit longer hair, and facial hair, helped to blend in with the targets of the investigation. Since I’d been to court to testify in a trial on the day the picture was taken, I’d worn a coat and tie. Unfortunately, for me, this foot chase occurred in the summertime and it was extremely humid. On a typical day I’d have been in jeans, a t-shirt, and tennis shoes.

The picture was taken by a newspaper reporter who somehow managed to show up just as I captured an escapee from a prison located twenty miles or so from the city. I’ve never understood how reporters always seem to find you, when backup cannot.

Anyway, I’d just left court and was on my way back to my office when I spotted the guy walking along the railroad tracks. He saw me and took off like a rabbit. I jumped from my car and chased him through neighborhoods, over a short fence, under a taller fence, through alleys and parking lots, and finally into someone’s unlocked apartment. After a brief and quite intense struggle while listening to nonstop screaming and squalling coming from the two women who lived in the apartment, I handcuffed the escapee and proceeded to walk the long trek back to my car. Of course, I’d jumped out of the car without grabbing my portable radio, so backup had no idea where I was. Not a smart thing to do. Couldn’t blame them … this time.


Signs like the one above are reminders for the officers who sometimes have a tendency to forget the details.

Officers must lock their weapons inside a lockbox before entering the booking area. This is to prevent prisoners from gaining control of a firearm. The officer locks the box and takes the key with him.

Lockbox at entrance to booking area.


Officers, in this case a deputy sheriff, secure their weapons inside a lockbox whenever they deal with prisoners.

Arrested persons are often seated and handcuffed to benches while waiting for processing. Notice the handcuffs attached to the second rail from the left, below.

Prisoners are fingerprinted for both in-house records and for the FBI national database. Most departments now use automated fingerprinting devices, such as this LiveScan terminal.

Capturing a suspect’s fingerprints on a LiveScan terminal

Prints are transferred to a computer terminal where the suspect’s personal information is entered.

Digital images replace ten-print cards (cards used for capturing inked fingerprints).

Some departments still use the old ink and ten-print card method of fingerprinting (LiveScan terminals are expensive).


Then, with the processing complete, prisoners are placed into a holding cell until they post bond, or until they are transferred to the county jail to await their first court appearance, usually an arraignment.

Police department holding cell.

Steel plates mounted on the walls serve as beds. Prisoners are issued mattresses if their stay is overnight.

Combination sink and toilet

In-cell telephone

When prisoners are transported from the lockup to a county jail, or for court proceedings, they’re often placed in full restraints—handcuffs, waist chain, and leg irons, like those pictured below.

The deputy pictured above unlocks a holding cell door to begin shackling prisoners for their court appearances. The deputy is armed, as you may have noticed, but this is a staged photo taken by me for the purpose of educating writers about the process. In a real situation his weapon would be in the lockbox. There were no prisoners inside the cell at the time we took the photograph.



Detective Pete Gitterdone had a spotless attendance record, never missing a day for sickness during his entire thirty-three years with the department. He was so proud of his achievement, in fact, that he refused to stay at home on this particular day, a time when his fever hovered at 102.

Coughing and sneezing fits forced him to spend the majority of the morning with his mouth and nose buried deep into a crumpled, crud-dampened, and extremely yucky handkerchief.

Gitterdone, feeling all achy and fatigued, was busy collecting suspected blood samples (brownish red stains for the official record) at a particularly brutal homicide scene, alternating between hacking and achooing, when his partner, Detective I. Lergictowork, told him he looked sickern’ a dog, like death warmed over, and asked if he needed a break.

Gitterdone promptly turned his head away from his partner and fired off a round of wet sneezes directly into the large paper bag of already-collected evidence. “No,” he said. “I’ll be okay. Besides, I’m almost done. Just a couple of prints to lift and I’m outta here.”

He tipped his head toward a desktop where a few sheets of yellow legal pad paper sat among a scattering of pencils, pens, and colored paperclips. “Looks like the suspect might’ve touched these papers,” he said. “How ’bout handing me a can of Ninhydrin. There’s one in my kit.”

Ninhydrin reacts with amino acids to produce a purple reaction product called “Rhuemann’s Purple”. It is useful on porous surfaces—especially paper. ~ Sirchie

So, did you notice anything particularly wrong with Gitterdone’s method of evidence collection? If so, what?

After watching these two work, well, it might be a good idea to have both Gitterdone and Lergictowork read this list of Crime Scene Do Nots. It might help to have your protagonist take a peek as well.

Crime Scene DO NOT’S

1. Do Not blow away excess fingerprint powder! Doing so adds your DNA to the surface.

2. Do Not use Styrofoam to package electronic devices (computer parts, etc.) because it can cause static charges. Instead, use foam padding or bubble-wrap.

3. Do Not alter or add anything to a crime scene sketch after leaving the scene. Memories are not quite as accurate as we may think.

4. Do NOT place bloodstained evidence in plastic bags. Plastic bags and containers can serve as incubators for bacteria, which can destroy or alter DNA. Rule of thumb – paper bags/containers for wet evidence (blood, semen, saliva, etc.) and plastic for dry evidence.

5. DO NOT collect DNA evidence samples (saliva, blood, etc.) from a criminal suspect without a court order, the suspect’s consent, or during exigent (emergency) circumstances.

6. Do NOT cough, sneeze, exhale, etc. over any evidence sample. This also includes talking over a sample. With each word spoken comes your DNA that’s instantly transferred to the sample.

7. Do NOT fold wet documents. Leave that to the professionals in the lab.

8. Do NOT use fingerprint tape or lifters to collect bits of trace evidence. The adhesion on print lifting tape is insufficient for picking up tiny bits of evidence.

9. Do NOT use dirty digging tools when collecting soil samples. Always clean tools thoroughly after each use to avoid cross contamination.

10. Do NOT use fingerprint lifters in lieu of gunshot residue (GSR) collection materials. (see number 8 above)


Fingerprint lifter – Sirchie image. I used Sirchie lifters all the time during my career. In fact, I still have a few leftover from my crime-solving days.

11. Do NOT allow shooting suspects, victims, witnesses, etc. to wash their hands or rub them against other surfaces until after GSR tests/collection have been completed.

12. ALWAYS remember #6 – Do NOT cough, sneeze, exhale, talk, etc. over any evidence sample.

Bonus – Transferred Prints

Do NOT write a transferred fingerprint scene without first giving it a ton of serious thought. Here’s why:

Yes, it is indeed possible to transfer a fingerprint, even accidentally. However, a skilled examiner should be able to spot duplicates since they tend to appear very thin and thready. Also, the background area surrounding the “new” print may not match the surface of the place where the transferred print was left. Background pattern(s) transfer along with the print.

Here’s where writers often make their mistakes when setting up characters to “take a fall” for another character. Transferred prints are mirror/reverse images and would be easily recognized by a skilled examiner. It’s possible, though, that an inexperienced print examiner, one who’s new to the field, may not catch it right away. But that scenario is highly doubtful.

BIG, BIG, BIG Writers’ Police Academy news is on the way. The 2019 WPA is a special event, one unlike anything we’ve presented in the past. And when I say special, I mean it’s over the top S.P.E.C.I.A.L.! I am so pleased and thrilled to present such an exciting opportunity for writers. This has never been done before, not ever!

For now, though, I’d like to share the dates and the location so you can make plans to attend. Please keep in mind that due to the nature and location of this unique program space/slots are limited. We’ll soon begin to announce more specific details but, for now …

Date – August 1-4, 2019

Location – Raleigh, N.C.


Especially for you, a J-N guide to fingerprinting … and more.


JFI – Journal of Forensic Identification.

JFS – Journal of Forensic Sciences.

Joint – Hinged area where two bones are joined together.


Keratinocyte – The major cell found in the epidermis.

Keratins – Highly insoluble fibrous proteins found in skin-related structures such as hair, wool, hooves and horns, claws, beaks, and even feathers.


Latent Print – Friction ridge detail (fingerprint) that is not readily seen by the naked eye.

Law of Biological Uniqueness– Scientific Law stating that all items in nature are unique.

Leuco Rhodamine 6G – Reagent that reacts with the heme moiety of the hemoglobin of red cells in blood. It’s used to enhance and visualize fingerprints left in blood.

Leucocrystal Violet – A colorless form of gentian violet used to stain blood residue on both porous and nonporous items.

Lift– An adhesive or other vehicle used to transfer a friction ridge imprint (a fingerprint) from a surface.

Lights Out – Computer process where the AFIS computer automatically obtains friction skin features, searches the AFIS system, and presents an identification or exclusion based on a predermined score. No human is involved in this process.

Liquid Nitrogen – In its liquid state (-195 degree C), liquid nitrogen is ideal for the separation of adhesive surfaces.

Liqui-drox – A fluorescent yellow solution used to develop prints on both sides of dark-colored adhesive tapes.

Locard’s Principle of Exchange – Edmond Locard’s Principle of Exchange states that when any two objects come into contact, there is always transference of material from each object onto the other. (People entering a crime scene both leave and take away evidence, in some form).

Loupe – A small magnifying glass used in the identification and comparison of fingerprints.

Luminol – Chemical that glows with a bluish tint when it comes into contact with blood. it can detect blood at 1 part per million. It’s so sensitive, in fact, that one drop of blood within a container of 999,999 drops of water, will cause luminol to glow.


MC’s – Major Case Prints.

MMD – Multimetal Deposition, a two step process using a colloidal gold and a physical developer solution to enhance latent prints.

5-MTN – Methylthioninhydrin, a reagent that reacts with amino acids to develop prints on porous items.

Medial Interphalangeal Flexion Crease – The middle crease on a finger.

Metacarpo-phalangeal Crease – Creases where the fingers meet the palm.

Microburst Method – Developed by the FBI, this method of developing prints is designed to expose a nonporous item to a large amount of Cyanoacrylate (Superglue) fumes for a small amount of time. The Superglue is positioned into a chamber heated to temperatures above 300 degrees. The item to be printed is then placed in the chamber for 30-45 seconds.

Minutiae – Small details.

Molybdenum Disulfide – Chemical used to prepare Small Particle Reagent (SPR). SPR is a means to develop latent fingermarks on wet, non-porous surfaces such as glass, plastic, metals and even the sticky sides of tape.


NCFS – National Commission on Forensic Science.

NCIC – National Crime Information Center. To learn more about NCIC, click here.

NFB – National Fingerprint Board of England and Wales.

NV – Abbreviation for “No Value,” meaning a print has no value for identification purposes.

Stay tuned for exciting Writers’ Police Academy news. In the meantime, space is available so please hurry. Sign up today. This year is absolutely incredible!!



Especially for you, an A-D guide to fingerprinting … and more.

A-Naphaflavone– chemical used in fixing Iodine processed friction ridge detail.

AFIS– Automated Fingerprint Identification System.

ALPS– Automated Latent Print System.

ALS– Alternate Light Source.

APIS– Automated Palmprint Identification System.

Acid Fuchsin– Reddish protein stain used to enhance bloody friction ridge detail. Also known as Hungarian Red.

Acid Yellow 7– A fluorescent dye stain used to develop latent prints left in blood on nonporous surfaces.

Adermatoglyphia– An extremely rare genetic lack of fingerprints.

Alternate Black Powder– Developed by the FBI in the 1990’s. this powder is used as an inexpensive, yet quite successful means of developing ridge detail on adhesive surfaces and/or various types of tapes.

Amici Curiae– Latin for “friend of the court.”

Anhidrosis– A medical condition that decreases or eliminates the capability of the body to sweat.

Ardrox– Fluorescent yellow dye used with UV light to see cyanoacrylate-fumed (Superglue) friction ridge detail.

Battley Classification System– Classification system for single fingerprints. The system was used in the 1930’s.

Benzidine– Benzidine, a carcinogen, was once considered as the best technique for developing bloody latent prints on nonporous items. However, due to serious health concerns, it is no longer used.

Bifurcation– Point where one friction ridge divides into two friction ridges.

Boiling Technique – Method to re-hydrate the friction skin of a deceased person. This is exactly how it sounds. To rehydrate friction skin, investigators bring water to a boil, remove it from the heat, and then submerge the hand of the deceased in the hot liquid for five seconds. The hand is then removed and dried. The skin should now be successfully hydrated to the point where it’s possible to capture a readable print. If not, the process is repeated.

In the caldron boil and bake;
Eye of newt, and toe of frog

  Wool of bat, and tongue of dog,
Adder’s fork, and a … dead man’s hand?


Bracelet Creases– These are the creases/wrinkles located at the base of the palm, where the hand meets the arm. This is typically the spot where friction ridges end.

CA or CAE– Cyanoacrylate (Superglue). An adhesive that, when heated, its fumes develop friction ridge detail.

Cadmium Chloride– A metal salt used to treat ninhydrin developed fingerprints.

Calcar Area– Area at the heel of the foot.

Cheiloscopy– The study of lip prints.

Chiroscopy– Examination of the hand.

Clandestine– Kept or done in secret.

Cluster Prints– A grouping of more than one print.

Collins Classification System– Classification system for fingerprints used by Scotland Yard in the early 1900’s.

Colloidal Gold– Reagent that reacts with amino acids to develop ridge detail.

Comparator– A split image screen used to view and compare fingerprints.

Core– The center/middle of a fingerprint pattern.

Diaminobenzidine– Reagent used to spot and develop bloody friction ridge detail. Also known as DAB.

DPR, or Dermatopathia Pigmentosa Reticularis – a genetic disorder that’s handed down through the female side of the family. DPR is caused by a specific gene that mutates during embryonic growth. The result of the mutation is a lack of ridge detail and sweat glands.

Dactylography– Study of fingerprints as a method of identification.

Dactyloscopy– The comparison of fingerprints for identification.

Degloving– The unintentional separation of the skin from the hands or feet. This unintentional parting of skin and flesh/bone is often the result of a deceased’s body prolonged soaking in water. The skin that slips from the hands and feet typically slides off in a manner that resembles a glove. However, such slippage of skin may also occur in severe forms of inherited mechano-bullous disorders called epidermolysis bullosa.

Dermatoglyphics– The study of the surface patterns of the skin.

Dragon’s Blood Powder– Fingerprint powder made from the rattan palm resin. Greatly increases the probability of seeing latent prints on light, dark, and colorful surfaces.

Processing fingerprints is not alway a simple matter of dipping a brush in a bottle of black powder and then dusting the walls of the homes of notorious bad guys, such as the charming abode of tough guy Ima Stuffstealer.

For example, here are just two of the seemingly endless methods of print development.

DFO (1,8-Diazafluoren-9-One)

DFO is used to develop latent prints on porous surfaces. (click the links throughout this article for additional information and photos)

DFO reacts with the amino acids in perspiration. When this reaction is complete, the developed latent prints will fluoresce with the use of a laser or an alternate light source.

Equipment Used

Scales, graduated cylinder, magnetic stirrer and stirring bar, glass tray, sprayer, laser or alternate light source, oven or iron, dark storage bottles

Materials and Chemicals

• Methanol
• Ethyl acetate
• Glacial acetic acid • Petroleum ether

Mixing Procedure

DFO is mixed in two solutions—stock and working.

DFO Stock Solution

DFO … 1 g

Methanol … 200 mL

Ethyl acetate … 200 mL

Glacial acetic acid … 40 mL

Combine the ingredients and place on a stirring device for approximately 20 minutes until the DFO is dissolved.

Working Solution

Dilute the stock solution to 2 L with petroleum ether. The working solution should be a clear gold color.

Processing Procedure

DFO can be dipped or sprayed. When a specimen is processed with DFO, it must be dried and placed in an oven at approximately 100 °C (212 °F) for 20 minutes. If an oven is not available, a dry iron may be used (e.g., a steam iron with the steam turned off).

Sergeant Printz

LCV (Leucocrystal Violet)

LCV is used to enhance visual prints (click the link to read more about LCV) and develop latent prints deposited in blood.

*Cyanoacrylate fuming (Superglue) may be detrimental to this process. (click the links throughout this article for additional information and photos)


Scales, beakers, magnetic stirrer and stirring bar, sprayer, tissues or paper towels, dark storage bottles

Materials and Chemicals

• Leucocrystal violet (dye content ≥ 90%) • 5-Sulfosalicylic acid (purity ≥ 99%)
• Hydrogen peroxide 3% solution
• Sodium acetate

Mixing Procedure

Hydrogen peroxide 3% … 1000 mL

5-Sulfosalicylic acid … 20 g

Sodium acetate … 7.4 g

LCV … 2 g

Combine ingredients in the order listed and place on a stirring device for approximately 30 minutes.

Processing Procedure

Spraying is the most effective method of application. When spraying, use the finest mist possible because excess application may cause overdevelopment or running of the bloody print. Spray the specimen(s)— the development will occur within 30 seconds—then blot the area with a tissue or paper towel. When the area is dry, the preceding steps can be repeated to possibly improve contrast.

When using the LCV process in direct sunlight, any developed print should be photographed as soon as possible because photoionization may occur, resulting in unwanted background development.

No Double-Dipping!

Prior to dusting for prints investigators should dump/pour a small amount of print powder onto a piece of clean paper. The use of this powder prevents dipping the brush back into the bottle, a means of cross-contaminating the remaining powder (in the bottle) with DNA and other foreign substances.


*Source – FBI “Processing Guide for Developing Latent Prints”


The 2017 Writers Police Academy marked the second time I was lucky enough to present This year I had the honor to present workshops on Blood Spatter analysis and Fingerprinting.

As usual, before I started my first session I felt under prepared. I teach these topics on a regular basis to folks going through police training. To get ready, all I did was take materials I already hand and cut stuff out to fit in the session time of just over one hour. Then self-doubt hit, I feared I had cut too much information and my sessions would run short.

Wow was I in for a surprise. In every session, I ran out of time! I forgot how many amazingly good questions WPA participants ask.

As an Academy instructor, there is always pride in hearing about former recruits doing good as officers. That same pride bubbled up every time someone thanked me for a tidbit they used in a story.

During the blood spatter class I was able to do a demonstration of blunt force trauma using a spatter head.

Blood Spatter/Investigation

One the points I made in class was saying there was a certainty unpredictability about what will happen during a bloodletting event. Body composition, hydration levels, and other factors can alter characteristics of blood. This proved correct with each session.

In the first session, fake blood was flung nearly all the way across the classroom.

Bloodstain pattern session. Dexter-style (photo – Ry Brooks)

In the second session, it only flew a few feet.

Regardless by the squeaks of joy coming from participants it seemed they had fun watching my dummy (who I call Daryl) getting his skull beaten in.

The fingerprinting sessions while less exciting provided some thought provoking questions. During the sessions, I told the story of Brandon Mayfield, a person suspected of a terrorist bombing due to an error in fingerprint matching. In each session, I saw eyes widen as if the story sparked an idea for writers in the room.

Both days went fast, and soon it was time for the banquet. Walking towards the banquet, I was stopped by someone who said they were a first-time attendee. She wanted to ask a question not covered in the sessions. It was about home life and the ability to see my children play sports if on duty. I enjoyed every question I get but overjoyed to spend time humanizing the badge.

It seems the human facet of cops is one aspect of the WPA that does not get enough attention. There are countless books, videos, and web pages to research police procedure. Until folks meet a few officers and honestly take some time to talk to us people never fully “get” police personalities.

My only regret from the weekend was not being able to attend any session. With teaching multiple topics multiple times a day, I never got to go sit in on any of the other sessions. Also, personal and professional responsibilities kept me away from most of the evening events at the hotel.

Hopefully next year I will be invited back to present again. Until then my inbox is always open for questions or feedback, rj@rescuehumor.com

RJ Beam is a Law Enforcement professional and author from Wisconsin. He has experience both as a firefighter and police officer. During most of his career, RJ served as an evidence technician, processing crime scenes.

In 2003, he started writing by launching his blog www.RescueHumor.com. Over the years RJ was asked write articles for various police magazines and journals. He has released two novels in his Stuart Thompson series, Fire Cop in 2015 and Cops & Stalkers in 2017.


In the world of make believe, the place that exists in the minds of writers and readers alike, THIS is how the story begins … for the savvy writer. So go full screen, crank up the volume, and hit the play button. Oh, and please do watch to the very end (after the credits). You know how I like twists and surprises!


For details – Writers’ Police Academy


Fingerprinting birds. Sounds crazy, right? I mean, why would someone need to lift a print from a bird? Would an Emu stand still while a crime scene investigator dumped fingerprint powder on it’s beak? Probably not.

Have a seat for a moment and I’ll explain. This is good stuff, starting with …

Chicken Thieves

Years ago, chicken thieves were considered as the lowest of all crooks. After all, stealing someone’s chickens was to take away a family’s source of meat and eggs and even income if the farmer sold his birds to help make ends meet.

Therefore, it was not at all unusual for the local sheriff to receive a call about the shooting of a chicken thief. That sort of “farm justice” was unofficially permitted back in the day, because, well, why not?


But it was easier to catch chicken thieves back then than it is to catch modern day bird bandits, the bad guys who poach or kill birds of prey and/or steal their eggs. The eggs, by the way, are most often sold to collectors known as “eggers.”

Eggers go to great lengths to obtain their prizes, climbing tall trees to reach hidden nests and venturing into other even more dangerous situations. For example, in 2006, a 63-year-old egger named Colin Watson fell to his death while climbing a 40-ft tree in search of eggs. Watson, by the way, had been convicted six times in the past, and for over twenty years was on the radar of authorities.

During a raid in 1995, police discovered a collection of over 2,000 eggs in Watson’s home.

The number of egg collectors has decreased over the years; however, the poaching of birds of prey has increased. Many of those killing these magnificent animals are ranchers and farmers who shoot, trap, and poison the birds who hunt on their land.

In the past, all officials could do was to collect the bodies of dead birds, many of which were discovered in odd places, places where deceased birds shouldn’t be found—at the bottoms of ravines, etc. In other words, they were found in locations and in positions that made it obvious they were placed or tossed there by humans who were attempting to hide their crimes.


DNA and toxicology testing are extremely valuable when investigating crimes involving wildlife (toxicology tells us an animal was poisoned and DNA can help establish whether an animal was involved in an attack, or not), but they’re not useful when it comes to pointing toward a lawbreaker. So …

A PhD student, Helen McMorris, at Abertay University (Dundee) has found a means to develop and record human fingerprints on bird feathers. The exciting discovery will now assist law enforcement with their investigations

In a recent interview, McMorris said, “The structure of a feather is very similar to the fine weave structure of some fabrics such as silk. It has recently been found that fabric with a thread count of three per millimetre can sustain a fingermark or grab mark and, after microscopic examination, it was found that bird of prey feathers have a barb count of three per millimetre, suggesting that they could sustain a fingermark.”

During her research, McMorris found that green and red magnetic-fluorescent fingerprint powder produced the best results when excited with a blue wavelength of light and viewed through a yellow filter. Doing so causes prints to fluoresce.

Bingo! If the person’s prints are on file, well, police would then have their suspect. At the very least, a fingerprint on a wild bird of prey’s feathers 100% proves a human touched the animal, telling authorities it was most likely man, not natural causes, that killed the bird.

From the lighter side of today’s news … sarin gas, fingerprinting is hard work, and hacking.

Protecting Against Toxic Chemical Attacks

  • Scientists have successfully developed MOFs capable of deactivating toxic nerve agents. MOFs (metal-organic framework) are minuscule, porous structures that have large surface areas that allow for the absorption of gases and other materials. These MOFs also contain zirconium, which acts to neutralize toxic material, such as sarin gas.

A pinpoint-size drop of sarin on the skin is a lethal dose.

Using polypropylene, the stuff used to make plastic bags, along with thin layers of aluminum, titanium or zinc oxide. to make a protective coating for clothing material, researchers found that the treated-cloth successfully deactivated applied toxins. This is fantastic news for first-responders and soldiers. And us, to, if North Korea finally builds a slingshot large and powerful enough to lob a couple of sarin-gas-filled basketballs in our direction.

Perhaps it’s time to purchase and send gift cards for a shopping spree at that popular store, Gas-Masks-R-Us.

Fingerprint Examiners

  • Fingerprint examiners are carefully selected for the job. In fact, it’s a special person who, for hour after hour, unapologetically stares at smudged ink and squiggly lines, all day long. The job is so demanding and specific that potential print examiners often must successfully complete a series of tests to get the first foot in the door. Next comes a certification course. Then, when all the classroom and practical training is said and done … it’s not an easy job.

Curious to know if you have what it takes to become a fingerprint examiner? Well, here’s your chance. Click the link below to see a sample of the test prepared by the U.S. Dept. of Commerce, National Institute of Standards and Technology. I think you might be in for a surprise.


Do You Have What it Takes to be a Fingerprint Examiner?

Hacking a Router

  • Malware named xLED can infect common routers, a move that enables hackers to leak information, passwords, files, etc., from computers, even those with firewalls and other security measures and systems. This malware bypasses all security measures.

The way this works is nothing short of a Mission Impossible sequel. The malware causes the router’s LEDs (the lights that signal status) to blink and pulse in various ways—codes, if you will. Then, via a hidden remote camera, or by accessing and using the camera on your laptop (also remotely controlled by the hacker), the hackers record and decode the LED flashes. The xLED malware can program the LEDs to flash at lightning-fast speeds – more than 1,000 flickers per second for each LED.

Here’s a handy bit of news that’ll make you feel all warm and fuzzy … Specialized malware can siphon data from from numerous devices, not just cellphones and laptops. For example, it can suck private information from computer speakers, headphone jacks, external and internal hard drives, computer fans, 3D printers, smartphones, and even, as I mentioned above, LED bulbs. Yes, the Russians have all your recipes, cat photos, and vacation pictures. And, of course, writers, the FBI also has your search history. Yes, they know …