Making a Good First Impression: Preserving Footprints In Snow and Mud

“Neither snow nor rain nor heat nor gloom of night stays these couriers from the swift completion of their appointed rounds.”

The familiar phrase above is actually from an ancient Greek work of Herodotus describing the Persian system of mounted postal carriers. The phrase is also inscribed on the James Farley Post Office in New York City, and is sort of the unofficial creed of letter carriers across the country.

Another group of people who closely adhere to those words are criminals. Yes, this menagerie of lawbreakers—pickpockets, robbers, rapists, murderers, and the like—pay no attention to the weather when planning and plotting their devious acts against property and their fellow humans.

And, when the criminals do their dastardly deeds, even in bad weather such as the snowstorms we’re experiencing on the East Coast, law enforcement officers must do what it takes to bring the offenders to justice. Unfortunately, crime-solving often involves traipsing around the woods in the mud, snow, sleet, and freezing rain while trying to find a footprint or two.

One method of identifying and locating a bad guy is to do as they did back in the old west, and that’s to track the thugs back to their hideouts. Sure, following broken twigs and disturbed vegetation is one method. Finding and making castings of footprints and/or tire tracks in the dirt and dried mud is another.

But what about prints in the snow? After all, we know that casting materials generate heat, which causes snow to melt and deform the impressions left by footwear.

So how do investigators overcome the challenge of melting snow in and around footprints?

Well, our good friends at Sirchie have the perfect solution to the problem.

A squirt or two of Sirchie’s Snow Impression Wax provides an insulating medium between the heat-generating casting material and the surrounding snow. Once the spray contacts the snow it locks in the impression details while the casting material hardens.

Shake-N-Cast (center in photo below) is a kit containing a pre-measured water pouch and dental stone.

Apply pressure to break the water pouch and then shake to mix the two ingredients. No messy containers and no casting material on a detective’s shiny shoes. There’s enough material in a kit to cast an adult-size shoe up to 15″ long.

Metal casting frames are adjustable to fit all shoe sizes and most tire treads.

While we’re on the subject of impression evidence, the spray above—Dust and Dirt Hardener—is used to strengthen impression evidence (tire tracks, footwear impressions, etc.) found in loose or sandy soil.

The material keeps the soil intact under the weight of the casting material.

Finally, liquid silicone is often used for producing exact replicas of various impressions, including tire and footwear, jimmy marks, and even fingerprints.

Liquid Silicone is incredibly temperature tolerant, and can withstand cold down to -70F and heat to +500F.

The material sets within three to five minutes.

So there you go. Now your fictional CSI team need not worry about collecting evidence in the snow, or mud. Well, as long as they keep a can Sirchie’s Snow Impression Wax handy.