If The Shoe Fits – Impression Evidence

If the Shoe Fits

Detectives look pretty darn silly walking into court carrying a pair of plaster footprints. But, footprint and tire impressions can be extremely helpful to an investigator’s case. They’re especially helpful when the casts are a perfect match to the shoes the defendant chose to wear to the hearing. Yep, that’s actually happened.

Collecting impression evidence isn’t all that difficult, even in mud and snow, if you’ve got the proper tools. Here’s a look at the process of collecting footprint evidence.

Investigators usually keep an impression casting kit in the trunk of their police car.

Impression casting kits contain a casting material that’s similar in composition to the material dentists use when making impression molds for dentures.  The kits also contain dust, dirt, and snow hardener.

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Dust and dirt hardener firms up loose soil.

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Snow impression wax prevents snow from melting during the casting procedure.

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Casting powder is mixed with water and then poured directly into the impression.

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Hardened cast of suspect’s footprint.  The cast is used to identify a suspect’s shoes by size and unique characteristics, like cuts and indentations.  The cast also becomes part of the evidence that’s used in court.

12 replies
  1. Lee Lofland
    Lee Lofland says:

    I’ve heard that story, but I’m not sure if it’s true. Could be. I’ve even told it during a few of my workshops.

    How about the cop who tells the combative suspect, “If you don’t put your hands on the top of your car I’m going to make your brother an only child.”

    Or, the officer who tells the irate speeder, “No, I don’t mind if you complain about me to the shift supervisor. Oh, did I mention that I’m the shift supervisor. Sign here, please.”

  2. mnboater
    mnboater says:

    Not sure if this is true, but my favorite sort-of-bad-guy story is about this cop that pulls over a woman speeding. She takes up an attitude and asks the cop, “I thought cops didn’t write tickets to pretty women.” The cop responses, “We don’t.”

  3. l.c.mccabe
    l.c.mccabe says:

    Lee,

    I would love to see posts about stupid things that dumb criminals have done.

    I’m sure that you could do a whole series of them.

    I know that someone I used to work with told me that his sister called him to make sure he watched an episode of “Cops.” That is because they had a dumber than a sack of hammers cousin that appeared in all his glory on the show.

    Turns out their cousin stole a water tank.

    The water tank was from a residence.

    He did not empty the water tank before stealing it.

    The water tank dripped water behind him, leaving a nice little trail which anyone could follow.

    The cops followed said trail right to his house and then the idiot claimed he bought the water tank from a hardware store.

    Riiiiiiight.

  4. Lee Lofland
    Lee Lofland says:

    I know. I never understood why people voluntarily drive up to check points when they know they’re drunk. Something psychological there about wanting to be caught, maybe?

  5. Terry
    Terry says:

    When I volunteered (means bringing desserts) to the Labor Day DUI stop, we heard stories about the folks who, when asked for drivers license & registration said, “Sure. Mind holding my beer?” while they dug them out.

    Bad enough these folks are dumb enough not to detour when they see the required warnings that there’s a traffic stop ahead.

  6. Lee Lofland
    Lee Lofland says:

    Linda – We could do an entire day about the stupid things done by bad guys. The list is endless.

    For example:

    There was this one guy who was on trial for drug dealing and the judge asked to see his photo ID. The idiot reached in his pocket and pulled out a driver’s license and a bag of crack cocaine.

    And how about the guy who broke into a store at night? He walked up to the security camera and stared into the lens for a minute trying to figure out what to do about it. You could almost see the lightbulb go off in his mind when the idea hit him. He smiled and covered the camera with his hat.

    I watched the tape, recognized the idiot, and drove to his house to pick him up.

  7. l.c.mccabe
    l.c.mccabe says:

    Wearing shoes to court that were used in a crime, that seems to typify the term of dumb criminal.

    Like someone wearing their high school varsity jacket with their name emblazoned on it when they hold up a bank.

    Linda

  8. Lee Lofland
    Lee Lofland says:

    Sometimes, a photo of patent or transferred prints is sufficient. Investigators might remove a section of carpet if they need it for wet evidence testing – DNA, blood typing, etc. They might remove it just for the bloody footprints.

    I’ve even seen flooring, mattresses, doors, appliances and drywall removed from crime scenes. Whatever it takes to collect the evidence.

    Homeowners are rarely pleased to see pieces of their homes carted off to the police station.

  9. Terry
    Terry says:

    Interesting. Can you compare this with how you’d process prints that are indoors — maybe walking through blood, or dirt tracked in on a hard floor?
    For a bloody/muddy print on carpet, would you cut the carpet out and bring the piece to the lab? I’d think a homeowner wouldn’t be happy with that method.

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