forensics

FW: “Have you been fingerprinted?”

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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 – 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.

 

 

 

FW: “Have you been fingerprinted?” Read More »

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

 

 

 

 

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KN, p. 218 “What Does the Federal Bureau of Investigation Do?”

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“The Federal Bureau of Investigation (FBI) is an intelligence-driven and threat-focused national security organization with both intelligence and law enforcement responsibilities.”*  It is the chief fact-finding branch of the Department of Justice and helps other agencies by sharing that information and providing training.

Its mission is:

“To protect the American people and uphold the Constitution of the United States.”*

In 1908, the United States had about 100 cities with 50,000 people. The rest of the population (about 83 million) was spread throughout the rural areas of the country. Law enforcement personnel at the local level were often poorly paid (and were sometimes volunteer) members of the community. Murders were handled by local investigators and still are to this day. For the majority of the cases, murder is not a federal crime, unless carried out across State lines.

Prosecution of border security issues or organized crime was limited in 1908 since there was no adequate way to enforce the law at a national level. In fact, few criminal laws even existed at a federal level. For the most part, individual States and local jurisdictions handled their own criminal investigations, and sometimes that led to political corruption, corporate criminal behavior, and even slave labor in factories. Federal agencies were stretched thin or were nonexistent in some parts of the country.

President Teddy Roosevelt supported the idea of modernizing law enforcement, so when his Attorney General hired 34 of his own investigators (including nine seasoned Secret Service agents) to assist the Department of Justice, Roosevelt wholeheartedly endorsed the action. A few months later, the Bureau of Investigation was officially created. Hardly a large force, but it was a start.

At the beginning, incidents involving car theft across State lines, civil rights, and various kinds of fraud were the typical cases. The FBI also took on treason and domestic terrorism, and Congress (previously reluctant to loosen the purse strings) began to see the value of a national law enforcement agency.

It’s interesting to note that the Mann Act or “White Slave Traffic Act,” was passed in 1910 to help stop interstate prostitution and human trafficking, and the FBI had a role in the early investigations. One hundred years later, it has become an international problem and requires cooperation from many different agencies to obtain successful prosecutions.

World War 1 brought us the problems of sabotage by foreign agents against our military ships and munitions plants, as well as international smuggling. The FBI had entered the so-called spy business and worked hard to eliminate those threats.

 

In 1924, it was recognized that fingerprinting was a reliable way of connecting (or eliminating) individuals to a particular scene, and to collect that information in a central location would be helpful to other law enforcement agencies in the United States. Now, the FBI gathers and classifies fingerprints from convicted felons and other criminals, military personnel, federal applicants and employees, and shares that information with appropriate agencies. Additionally, fingerprints of military detainees and other persons of national security interest are being collected for national security purposes.

Formerly called Automated Fingerprint Identification System (AFIS), the program processes over 63,000 prints a day, is now integrated with other forms of identification and called IAFIS, and can deliver digital information in as little as two hours. It is used in connection with biometric databases (facial and voice recognition) for more accurate identifications. Next Generation Identification (NGI) combines biometrics, fingerprints, and palm prints to expand identification possibilities.

One of the programs developed by the FBI is the ‘Ten Most Wanted’ list. It began in 1950 as a way to call attention to fugitives who might otherwise remain at large. Each new list is posted in United States Post Offices and on the FBI website.

Since 1950, 518 fugitives have been on the list, and 484 have been apprehended or located. The stats below are from the FBI site:

    • 162 fugitives have been captured/located as a result of citizen cooperation.
    • Two fugitives were apprehended because of visitors on an FBI tour.
    • The shortest amount of time on the list was two hours, by Billy Austin Bryant.
    • The longest amount of time on the list was over 32 years by Victor Manuel Gerena.

With the advent of increased world-wide terrorism, the computer and cyber-security age, more complex corporate crimes, and a global awareness of human trafficking, the focus of the FBI has shifted.

At the end of 2017, there were over 35,000 employees, made up of intelligence analysts, field agents, language specialists, scientists, and information technology specialists. They are tasked with investigating:

  • Terrorism
  • Counterintelligence
  • Cyber Crime
  • Public Corruption
  • Civil Rights
  • Organized Crime
  • White-Collar Crime
  • Violent Crime
  • WMD (Weapons of Mass Destruction)

Stay tuned for posts about Quantico and training for the FBI, and interviews with former FBI agents.

 

*Photo and quotes credit: (from FBI website)

1969 Latent Print Match
A latent print removed from a 1969 murder victim’s car was later determined to be a match to the suspect’s fingerprint (inset) contained in the FBI’s Integrated Automated Fingerprint Identification System (IAFIS). The Houston police detective and Texas Department of Public Safety latent print technician instrumental in solving the cold case were honored by the FBI with the 2011 “Latent Hit of the Year” Award.

 

 

KN, p. 218 “What Does the Federal Bureau of Investigation Do?” Read More »

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