WPA

FW: “Have you been fingerprinted?”

August, 2019 note: I had occasion to return to SIRCHIE during MurderCon, a  Writers’ Police Academy event. While the instructors were different, it’s reassuring to note that the science remains the same. Read on for details about gathering fingerprints from paper.

 

People ask me all the time how I acquire the information needed to write Kerrian’s Notebook.

 

Simple answer: research. And lots of it.

 

If the questioners want to know more, I mention the conferences I attend, the reference books I read, the internet sources I’ve tapped into, and the experts willing to chat about their chosen fields. It’s a fascinating part of the job and I love it.

 

The next few posts will reveal some of the information gathered at a series of classes where I took photos and lots of notes. If you’re a regular follower of Kerrian’s Notebook, you may recognize some of the details mentioned here as having appeared on previous Detective Kerrian’s pages.

 

For all out fun, I go to the Writers’ Police Academy held in September – this was the 5th year at the Guilford County, NC location (my fourth). It’s a three-day, mind-blowing experience that demonstrates the nuts and bolts of police and fire and EMS procedure – taught by professionals and experts actively working in the field.

 

Along with several other strands of study, the 2011 WPA conference provided classes in bloodstain patterns, fingerprinting, and alternate light sources (ALS) conducted by Sirchie instructors. Because of the standing room only enthusiasm for these classes, Sirchie offered a five-day Evidence Collection training session for writers at their own complex in North Carolina. Sirchie makes hundreds of products for the law enforcement community and I felt this would be a great opportunity for Detective Kerrian to learn more about the latest and best gadgets being used to catch the crooks.

 I happily sent in my application and plunked down my credit card to hold my space in the class – ten months ahead of time.

 

On the first day of classes, our instructor, Robert Skiff (Training Manager/Technical Training Specialist at Sirchie) discussed the ‘CSI Effect’ – the pressure placed by the popular TV shows on real life crime investigation. TV labs and real life investigations bear little resemblance to each other – not in time, or equipment, or budgets. Then we got to work, using the powders and brushes needed to process a crime scene and used by actual techs in the lab.

Fingerprint powders, brushes and magnifier

It’s up to investigators and examiners to prove the case against the suspects, using proper evidence collection techniques and tools, because trace evidence is ALWAYS left behind.

 

Fingerprints found at the scene are still the favored piece of evidence tying the suspect to the crime. These days, using a combination of ingenuity and newly developed chemicals and powders, a crime scene investigator can lift (and/or photograph) prints from many previously challenging surfaces. 

 

By the way, black fingerprint powder gets all over everything when newbies are handling it for the first time. We must have used 50 wet wipes each during the morning alone.

 

After dusting prints with black fingerprint powder,

 

they were lifted from various smooth surfaces using (in forefront) a gel lifter, a hinge lifter and (in background) tape.

 

We had to be careful not to contaminate the powders and jars or smear the samples themselves before looking at the prints under the magnifier. By the end of the day, most of us had black eyes and streaks on our hands and faces. It looks much easier on TV.

 

Our prints were photographed and then viewed under an Optical Comparator. This machine can be hooked up to a laptop, and the image sent off to AFIS for identification purposes. No crooks in our crowd, so we omitted that step.

 

At the end of the first day we left happy, tired, and still wiping powder off our hands and faces. A tip from an investigator taking the class with us: add a cup of vinegar to the wash load to get those powder stains out.

 

Did I mention that we had loads of fun?

 

On the second day, Robert Skiff’s assistant for the class, Chrissy Hunter, passed out stainless steel rectangles and we pressed our fingers onto the plates, twice. First time – plain ole print, second time – ‘enhanced’ by first rubbing our fingers on our necks and foreheads to increase the amount of oils in the print. The ridge detail in the prints was so clear in the ‘enhanced’ version that there was no need to process them with powder. We lifted them with a gel lift.

 

If we were working a real scene, that might never happen, but it could. The usual occurrence is that partial prints are left at the scene and that’s what makes the search for the suspects so much tougher than what the TV dramas indicate. There is no instant ‘a-ha’ moment that comes 45 minutes after the crime has been committed.

 

The prints are generally sent off to be compared with the millions in the AFIS database, and here’s where TV parts with reality again. AFIS comes back with a list of 10-20 possible matches and someone then makes a comparison by hand of the most likely hits.

 

After practicing the basics, it was time to move on to fingerprint discovery on documents. There are scheming relatives who forge wills, less than loving spouses who murder for the insurance, bogus suicide notes, and the list goes on. How to prove the nefarious intent? Fingerprints. But…as we discovered the first day, fingerprint powder is messy and almost impossible to clean up. An important document could be destroyed in the search for evidence of foul play. Enter chemicals and alternate light sources (ALS).

There is a protocol for testing with chemicals. If the prints don’t show up with one chemical, then it is possible to try several others, but this can only be done in a certain order:

 

Iodine

DFO

Ninhydrin

Silver Nitrate

MBD

 

If used in this order, the sample won’t be compromised, even though treated several times over several days. We experimented with several chemicals with excellent results, but for the ‘wow’ factor, I’m showing the ones that look great on camera.  😉

Spraying Document

 DFO reacts to amino acids in the prints. We created our samples placing our own enhanced prints on plain white paper. We hung the papers in the fume hood, saturated them with DFO, then put them in the oven to bake for several minutes.

This DFO sprayed, baked sample doesn’t look like much, so it was time to use an ALS to really ‘pop’ the print and make it photo ready.

Alternate Light Sources vary depending on the scene lighting and/or need to highlight the evidence. A few used in the field are: the ‘poor man’s ultimate light source’ (a mag light), black lights, UVC lights, lasers, LED lights, Ruvis lights (cost about $20K), and pure white lights. Each has a specific quality that the investigators can tap when needed.

After we sprayed our samples with DFO and baked them in the oven, we darkened the room, and put on orange plastic glasses. Then we side-lit the sample with a 455nm light. The photo was taken at that point.

Same sample, side-lit at a slightly different angle. Photo taken through an orange filter.

 

Ninhydrin, the third chemical group in the list to be used if nothing has shown up yet, comes in several forms: acetone, zylene and Noveck.  Ninhydrin reacts to another set of amino acids and likes warm, moist air. If a sample is being saved overnight for processing, you can place it in a ziplock bag, blow into it, then seal it and still maintain its integrity.

 

Before working with any chemical, it’s a good idea to make copies of the document. Why are there different kinds of Ninhydrin? Zylene will run some inks. Acetone will run all inks, all the time. Ooops! There goes the document if you grab the wrong chemical, so copies are definitely necessary. Noveck is the clear winner when working with inks. It gets fast results and dries quickly. Additionally, it can be sprayed on an outer envelope to reveal what’s inside. Without damaging either piece of paper. Very cool.

Ninhydrin-Noveck sprayed on outer envelope

 

You could see the plots developing in our writerly minds as the Noveck dried and the words inside the folder faded from view.

 

 

 

 

*Photos taken by Patti Phillips at the Sirchie Education and Training Center in Youngsville, North Carolina.

 

 

 

KN, p. 82 “Is that your footprint?”

 

 

 

 

It’s been raining off and on for days. It rained last week during a party, and people were tracking water and a little mud from the driveway runoff onto the porch all afternoon. We had so many different kinds of footprints that it would have made for a great crime scene demonstration.

 

Because, one of the most overlooked pieces of evidence at a crime scene is created by footwear.

 

Imagine: If a window breaks as a thief enters the premises during the commission of a burglary, the glass will fall into the house, and onto the floor or rug below the window. When the thief steps through the window, unless the thief has wings, he/she will probably plant a foot right in the middle of the glass. And walk through the house, most likely tracking minute pieces of that glass. That glass may also become embedded in the grooves of the sole of the shoe, creating a distinctive footprint.

 

If the investigating officer can place a suspect at the scene with the footprint, then there is probable cause to fingerprint that suspect and hopefully establish a link to the crime.

 

A new method of eliminating suspects right at the scene involves stepping into a tray that contains a pad soaked with harmless clear ink that doesn’t stain, then stepping onto a chemically treated impression card. No messy cleanup, immediate results, and it can even show details of wear and tear on the shoe. This can be a way to establish a known standard (we know where this impression came from) to compare with multiple tread prints at the scene.

Footwear Clear Ink Impression

 

 

Another tool for creating a known standard is the foam impression system. It takes a bit longer, (24 hours) but clear, crisp impressions can be made, including of the pebbles and bits stuck deep into the grooves and the writing on the arch. Very helpful when trying to place suspects at the scene. A rock stuck in the sole is a random characteristic that can’t be duplicated, so becomes another point of identification.

 

This is how it works: Somebody steps into a box of stiff-ish foam – a bit like stepping into wet sand.

 

An impression is made instantaneously. The detail is great – down to the wear on the heel.

Pre-mixed dental stone (made with distilled water and the powder) is used to fill the impression.

It takes 24 hours for the cast to become firm enough to pop out of the foam. We now have a permanent record of the footwear tread, which could be used for comparison to other prints found at the scene.

Footwear Casts

 

Occasionally footprints are found on the ground outside a window or in the gardens surrounding a house after a burglary or homicide. Ever see a crime show on TV where the fictional investigator makes a snap judgment about the height and weight of the owner of the footprint because of the depth of the impression? That’s merely a plot device and is not scientific evidence in real life. A crime scene photographer or investigator can photograph the footprint (next to a measurement scale), make a take away cast, and then compare the impression with those of the suspects or other bystanders at the scene. Beware: making a cast of the print destroys the print, so a photograph must be taken before pouring that first drop of dental stone.

 

Footprints can be found at bloody crime scenes as well. The suspect walks through the blood, tracks it through the house, cleans it up, but the prints are still there, even though not obvious to the naked eye. Blood just doesn’t go away, no matter how hard you try to get rid of it. It seeps into the cracks and crevices of a floor and even behind baseboards.

 

A savvy investigator will collect sections of carpet (or flooring) taken from where the suspect might have walked during the commission of the crime, then conduct a presumptive test for blood (LCV – Aqueous Leuco Crystal Violet), find a usable footprint, compare it to a known standard, and then be able to place the suspect at the scene.

 

 

 

 

Be careful where you walk. That footprint can be used as evidence.

 

 

 

*Photos taken by Patti Phillips

 

 

 

 

KN, p. 240 “The SWAT Team Experience”

 

S.W.A.T. stands for Special Weapons and Tactics, implying a special level of training and weaponry for the team members. When we hear that a SWAT team has been deployed, we know that a serious law-enforcement-required incident and threat to public safety has occurred, which may be beyond the scope of the typical police department or first responder.

 

The Los Angeles Police Department (LAPD) has the reputation of creating the first SWAT teams in the USA, but Philadelphia coined the Special Weapons and Tactics phrase first, in 1964. Philly established a large team whose sole responsibility was to combat the rising number of bank robberies in the city, hoping to stop them in progress. LAPD organized their own program around the same time, but the focus was different, using their teams during civil unrest and riots, when people attacked police and attempted to overwhelm them from all sides.

 

SWAT team members always have experience in other agencies or departments before applying to and being accepted into this specialized arena.

 

Depending on the needs of the towns/counties, SWAT teams are larger or smaller, relative to the size and needs of the rest of the police force. The Wichita Falls, Texas, Police Department SWAT Team members are trained in everything from Hostage Rescue to Dignitary Protection during a 60 hour basic SWAT school. Wichita Falls has a little over 200 sworn officers, with a SWAT team of 18. The Wisconsin department we observed was a 40 person department, with a SWAT team of 10, including two snipers.

 

A SWAT team is called out for:

 

  • Hostage Rescue
  • Barricaded Rescue
  • Suicide Situations
  • High Risk Search Warrant Services (i.e. drugs)

 

The team’s mission is to save lives. A hostage rescue is the most complex and the most man power intensive of the possible assignments. The goal is to end it sooner rather than later. If there is no hostage in the house, with just one person in an isolated place, then a negotiator might be used, since the safety of others and time considerations would not generally be a factor.

 

The National Tactical Officers Association (NTOA) sets the standard for the country for the management and protocols in a hostage situation. The participants are identified and divided into categories:

 

  • Hostages
  • Civilians (neighbors)
  • Law enforcement
  • Suspects

 

The civilians are cleared out before a SWAT assault begins. Other jurisdictions may be called in to help. Past experience has shown that in situations like school shootings or bank robberies where a number of people are involved, everyone, including small children, is asked to leave the building with hands up in the air. This way, the law enforcement groups on the scene will know that the children have nothing hidden in their hands and/or are not being used to create more chaos or danger for the waiting crowd(s).

 

It’s important to note that school patrol personnel might have been employed a few years ago to keep drug dealers off the campus just by their very presence, without any expectation of violent confrontation. Now, more and more often, they are being trained in active shooter scenarios in order to be pro-active in the minutes before a SWAT team can arrive.

 

A SWAT team member’s mindset:

The men and women in SWAT have a warrior mindset and are confident in the fact that they will get the job done, that they are the best candidates for the job, and they are not afraid of being under fire. For a set period of time (6-12 months in various departments) after training, Field Training Officers (FTO) guide rookie SWAT officers through the many different scenarios that may occur. Team members are always ready for the callout, so training is intense and constant. If the team stays trained and never gets called upon, that can be tough on morale – “when am I going to be able to show what I can do?” It’s like a fine-tuned machine that never gets used. In big cities, that would never be an issue, but in smaller, less populated areas with fewer SWAT-needed situations, it might become a factor.

 

Many of today’s police departments have a greater social work component to hostage situations than in the past, so a hostage negotiator gets involved before SWAT starts knocking down doors. Often, negotiators are specifically assigned to the SWAT teams.

 

There is a certain gender bias that women must fight against in the job, mostly because it is thought by some that a woman may not be strong enough or tough minded enough to carry through in a hostile situation. The capability to shoot is never in question, but sometimes the willingness to shoot is a factor in the negative thinking. The physical tests are not adjusted in most jurisdictions, so women must do the same pushups and gear carries that men do. In truth, women perform valuable functions on the SWAT teams in the roles of negotiators, even if they can’t pass the physicality tests to breach buildings. In general, women have been found to be more observant, better at interviewing than some men, and more emotionally aware at a crime scene, valuable attributes for negotiators.


If negotiations fail, and/or the hostages are at risk of being injured or killed, more aggressive methods are used.

 

Unless a police department is headquartered in a big city, SWAT teams are often part-time, coming together as a unit when needed, perhaps once a month. However, training continues whether there is a case or not. It’s important for safety and efficiency for the team to train as a group on a regular basis – In Neenah, Wisconsin’s case, they train together for about 16 hours a month.

                       

A team might be shared by other towns in a county, and the home town team members often perform other duties within the department until required for a bank robbery or other kind of hostage scenario. There just isn’t enough money in the budget for a small town to support a team they only need occasionally, but when SWAT is required, it’s essential that they be highly trained. It’s smart to share that capability.

 

 

Training, training, always training

You may have noticed photos of law enforcement officers on the front lines carrying large shields. The men carrying those shields must have excellent upper body strength, since they have to carry the shield in place with one hand and a rifle (or baton) in ready-to-fire position in the other. Try keeping your arms chest high in front of you, bent at the elbows, while holding ten pound weights in each hand. How long can you do it continuously without getting tired or losing focus?

 

Physical Fitness training needs to be done on their own time, and SWAT members make sure it gets done. Their lives and those of their team may depend on maintaining that strength, agility, and split second timing while carrying the 25-65 pound gear/equipment in all kinds of weather during attack or defensive actions.

 

A typical practice for snipers includes (while carrying a 25 pound pack)

  • 50 yard sprint
  • 25 yard high crawl
  • 25 yard low crawl
  • 20 push ups with the pack

 

Followed by a 2 minute break then (perhaps) 40 overhead lifts of that pack in 2 minutes.

 

Then, a two minute break followed by holding a plank position for 80 seconds.

 

Then, a standing broad jump of 6-7 feet, followed by a two minute break.

 

Then, a timed 1/4 mile run with the pack on the back.

 

Then, they repeat the whole routine in reverse.

 

 

*Many thanks to the Neenah, Wisconsin SWAT team members who shared their knowledge and experiences during a Writers’ Police Academy session held in Wisconsin.

 

Next up:  “SWAT Equipment and Strategies”

 

 

Scroll to Top