Douglas P. Lyle

Cheat Sheet / Updated 02-28-2022

Ever wonder just how prevalent various crimes are? Or about what you should do if you witness a crime? This Cheat Sheet covers that and more, such as how investigators approach a crime scene and the tools they bring to bear in their search for clues, as well as how the medical examiner or coroner determines the cause, mechanism, and manner of death.

Article / Updated 03-26-2016

Many criminals attempt to damage, alter, or remove their fingerprints to avoid identification or connection to prints found at a crime scene. From John Dillinger to more "common" criminals, these efforts are usually unsuccessful. Still, if, after leaving prints at a scene, the perpetrator successfully alters or damages his prints, the fingerprint examiner may not be able to make a reliable match. But do some people actually "lose" their fingerprints? Do they disappear? It seems that this does rarely happen. Certain activities, diseases, chemicals, drugs, and genetic disorders can flatten the friction ridges to such an extent that no print pattern is discernable. Bricklayers can literally "wear down" their finger pad ridges to the point that no pattern is evident. Even secretaries and file clerks who handle paper all day can have the same thing occur. Typists and piano players can suffer similar alterations. Diseases that severely affect the skin can also obliterate the ridge pattern. These would include scleroderma, psoriasis, and eczema, to name a few. Hairstylists, dry cleaning workers, and those who work with lime (calcium oxide) are often continually and repeatedly exposed to chemicals that can "dissolve" the upper layers of the skin and thus flatten the ridges. Drugs, particularly those used in cancer treatment, can eradicate prints. Chemotherapeutic agents such as capecitabine (Xeloda) would be an example. With prolonged use, the finger-pad skin can become inflamed, swollen, and damaged to the point that ultimately ridge detail disappears. The medical term for this is Hand-Foot Syndrome. Those who suffer from a rare genetic disorder called adermatoglyphia are born without friction ridges and thus have no fingerprints.

Article / Updated 03-26-2016

On April 5, 1994, the body of Kurt Cobain, singer/songwriter for the grunge rock group Nirvana, was found in an over-the-garage apartment at his home. His wife, Courtney Love, was in another state at the time of his death, so he was home alone. Or at least it appeared that way. He was found lying on his back, with a shotgun resting on his chest, and an obvious shotgun blast beneath his chin was the cause of death. A suicide note was found nearby. The manner of death was determined to be suicide. But was it? Many things about the scene were problematic for investigators. Kurt had large amounts of heroin in his system. The shotgun was in an inverted position on his chest so that the ejection port of the semiautomatic shotgun was to his right. Yet, the ejected shell was on the floor to his left. How could this happen? It is unlikely the shotgun spun around as it discharged, as the barrel was tightly gripped in Cobain's left hand due to fairly instantaneous rigor mortis, which can occasionally occur in such sudden traumatic deaths. Did someone kill him while he was heavily sedated by the heroin and then place the gun there to make it look like a suicide? Possible. Particularly since many believe that the suicide note wasn't really that at all but rather simply the ramblings that Kurt was famous for penning. Since then, the medical examiner (ME) and forensic toxicology communities have been divided over the true manner of death. One side feels that with so much heroin in his system, Kurt would not have been able to operate the shotgun and cause his own death. He was simply too wasted to do so. Others counter that since he was a chronic user, with multiple trips to rehab for heroin addiction, he could handle higher doses and still function as compared to someone who was a casual user, or someone who had never used heroin at all. They feel he could easily have taken his own life. The case remains controversial, and as yet is unresolved on these points. As you can see, the job of the ME and forensic toxicologist isn't always straightforward. Determining what drugs are present and in what amounts is critical, and usually fairly easy, but determining how that level of that drug affected the victim's abilities isn't always so clear. In the end, the ME and toxicologist must make a "best guess" as to the drug's true effects in the particular victim being examined.

Article / Updated 03-26-2016

For those interested in digging deeper into the science and techniques of forensic science and criminal investigation, here are some excellent resources for further study. The Writers' Forensics Blog This is DP Lyle, MD's blog. Though originally geared toward writers of crime fiction, this blog is followed by forensics industry professionals and those who have an interest in crime and forensic science. Lyle frequently posts about the latest forensic science technologies and criminal cases and other topics of interest to fans of science and crime. The site has been in existence since 2009 and is fully searchable by topics and keywords. Crime and Science Radio DP Lyle, MD and Jan Burke co-host this twice monthly Internet radio/podcast series. Each show presents an interview with one or more experts in the areas of forensic science and law enforcement, such as world-renowned forensic pathologist Cyril Wecht; Body Farm creator Dr. Bill Bass; best-selling author, forensic anthropologist, and creator of the hit TV series BONES Kathy Reishs; and Linda Fairstein, Chief of the NY County District Attorney's Sex Crimes Prosecution Unit, to name a few. All shows are archived so listeners can listen at their convenience. The Crime Lab Project The Crime Lab Project (CLP) is the brainchild of author Jan Burke and was established to raise public awareness of the many issues in the world of forensic science. From underfunding, to lack of quality control, to interesting criminal cases, this site is frequently updated with the latest information on forensic science and criminal investigation. Follow this blog or sign up for CLP's email alerts and stay in the front line of forensic science developments. The FBI Website This is the official website of the Federal Bureau of Investigation. Here you will find many links to how the FBI works, what services it provides, FBI job descriptions, crime statistics, the current Ten Most Wanted list, famous FBI cases over the years, and information on many areas of forensic science and law enforcement. Visit this site often or sign up for their updates to get up-to-the-minute info on all FBI activities. The American Academy of Forensic Sciences (AAFS) This is the official website of the American Academy of Forensic Sciences (AAFS), which offers information on jobs and education, as well as an extensive collection of lectures, slide presentations, and webinars that will greatly add to your knowledge base. The American Society of Crime Laboratory Directors (ASCLD) This is the official website of the nation's crime lab directors. The site contains information and links to a wide variety of information on crime labs worldwide. One of the most useful links, The Crime Lab Minute, which can be found under the Resource Library tab: The Crime Lab Minute, offers the current and the archived issues of their weekly newsletter. Each issue offers news about the society, current job opportunities, and, most importantly, breaking stories in the crime and science world. Forensic Magazine This is an excellent publication, available both online and in print. Its constant updates and excellent articles keep you informed and current on all things forensic science. It has an excellent Resources section that includes articles as well as video and webinar links. National Institute of Justice This site offers a wealth of information that is categorized on the home page. Check out all the links but in particular "All Topics A to Z" and "Forensic Sciences." Each category contains a long list of links to articles and other resources on virtually every topic in crime investigation. Digital forensics, DNA analysis, facial recognition, human trafficking, and forensic toxicology are examples of topics covered on this information-rich site. National Criminal Justice Reference Service (NCJRS) This extensive site offers a Browse By Topics List on its main page. Poking around in each category will lead you to information on essentially every aspect of forensic science and crime investigation. Topics include everything from forensic toxicology to identity theft to counterterrorism to crime scene analysis and much more. The Forensic Science Technician This site contains hundreds of useful links for anyone interested in forensic science and crime investigation. It's Articles tab offers links to many fascinating sites such as the Top 50 Forensic Scientist Blogs and many others.

Article / Updated 03-26-2016

Crime is a common occurrence in the United States. The FBI maintains a database of all reported crimes throughout the country. It's called the Uniform Crime Reporting (UCR) Program. During 2013, nearly 10 million criminal acts were reported. These crimes consisted of the categories and numbers shown in the following table. Crimes Number of Criminal Acts Violent Crime 1,163,146 Murder/Manslaughter 14,196 Rape 79,770 Aggravated assault 724,149 Robbery 345,031 Property Crime 8,632,512 Burglary 1,928,465 Larceny-theft 6,004,453 Auto theft 699,594 Source: Federal Bureau of Investigations

Article / Updated 03-26-2016

Do you know what to do if you witness a crime? In life, you just never know. You could be going to the store or a movie, maybe dropping the kids off at school, or perhaps sitting at your desk at work, and it happens — a crime occurs right before your eyes. Here's what you should do: Protect yourself. Run, call for help, or hide. Do what is necessary to keep yourself out of harm's way. Help others. Offer first aid to anyone who's injured. Call for help. As soon as possible, dial 911 to report the crime and to summon medical and law enforcement help. Don't touch or move anything. Remember that anything you touch or move can damage or contaminate critical evidence. Pay attention. Take a deep breath, relax, and look around. Notice people, what they look like, what they're wearing, any distinguishing marks they have, and what they're doing. Notice vehicle make, model, and license number, or any other distinguishing details, if possible. Wait for the police. When the police arrive, direct them to the crime and to any injured parties. Tell them exactly what you witnessed and answer all questions truthfully. Be careful to relate only what you know and don't attempt to help by filling in any gaps with what you believe should be true.

Article / Updated 03-26-2016

The most important function of the medical examiner in any death investigation is determining the cause, mechanism, and manner of death. Here are definitions of each of these terms: Cause of death: The disease or trauma that directly caused the victim's death. Examples include a heart attack, a gunshot wound to the head, or a drug overdose. Mechanism of death: The specific physiological derangement that actually led to the cessation of life. For example, a heart attack victim could die from a deadly change in heart rhythm or from severe damage to the heart muscle, leading to shock. Here the cause of death is a heart attack, but the mechanism is a cardiac arrhythmia or cardiogenic shock, respectively. Manner of death: How the cause of death came about. The five manners of death are natural, accidental, suicidal, homicidal, and undetermined. A gunshot wound (the cause of death), may have been accidental, suicidal, or homicidal, for example. Only deaths from disease are natural.

Article / Updated 03-26-2016

Crime scene investigators are called to all types of crime scenes and at all hours. Because they need certain tools and equipment to perform their duties, criminalists usually keep a well-stocked toolbox, which contains the items they most often need. The box may literally be a toolbox or tackle box, but can be anything that is easily carried to the scene. Here's what's in it: Crime-scene tape to cordon off the area A flashlight Latex gloves and paper shoe covers A magnifying glass and tweezers for collecting trace evidence A pen, logbook, and sketchpad Measuring tapes and rulers Digital camera, as well as a camera with black and white and color film and several different lenses An assortment of paper, plastic, and glass containers to store collected materials Sealable evidence bags Portable alternative light sources such as laser, ultraviolet, and infrared Basic fingerprint kit with powders and lifting tape Casting kit for three-dimensional shoe and tire impressions Gunshot residue detection kit Chemicals to locate occult bloodstains — such as Luminol Serology kit for sampling blood and other biological fluids

Article / Updated 03-26-2016

The medical examiner (ME), when dealing with death, is charged with determining the cause and manner of death. The cause is what actually led to the death; the manner is by whose hand and for what purpose the death occurred. These manners can be natural, accidental, suicidal, homicidal, or undetermined, the latter being designated when the ME can't assign the death to one of the other manners with any degree of certainty. The determination of the manner of death is not always easy and in some situations can seem odd. For example, can someone die from pneumonia yet the cause of death be homicide? How does a killer give someone pneumonia? Say a thief shoots a store clerk during the course of the robbery. The clerk survives but is paralyzed from the neck down and ultimately is placed in a neurological treatment center where such injuries are cared for. He is bedridden and dependent on the staff for everything from eating to bathing to changing positions in bed. Someone in this situation can linger for many years with proper care. The most frequent cause of death in such cases is an infection such as pneumonia, a urinary tract infection, or an infection in a bed sore (decubitus ulcer), which is caused by localized pressure from lying in one position too long. Each of these infections can seed the bloodstream and cause septicemia (infection in the bloodstream), which carries a high mortality rate. Say the clerk lives for 20 years but ultimately develops pneumonia and dies. What's the manner of death? Pneumonia is a natural cause of death so the manner must be natural, too. Right? Not necessarily. If the victim were not paralyzed and confined to bed, he likely would not have developed his fatal pneumonia as this is much rarer in healthy ambulatory people. So the pneumonia arose from his paralysis, which in turn occurred at the hand of the thief who fired the shot. So the shooting began the "cascade of events" that led to the victim's death. The manner of death could easily be deemed homicidal in this situation. And many cases have followed just such a pattern. In 1994, Scott Sittler was shot in the head in Santa Ana, California, and the resulting injuries left him quadriplegic. In 1996, Erwin Johnny Sanchez, his brother Giovanny Edgar Sanchez, and friend Daniel Paul Cruz pled guilty to attempted murder and were carted off to prison. But in 2009, Sittler developed pneumonia and died. The ME listed the manner of death as homicide, opening the door for murder charges against the three men.

Article / Updated 03-26-2016

The first officer to arrive at a crime scene must take certain steps to preserve life and evidence. Only after these duties are performed can analysis of the scene begin. These steps include: Ensuring the officer’s personal safety and that of any fellow officers, victims, suspects, and witnesses. Offering first aid to any injured persons and calling for medical help. Calling for backup and any ancillary personnel, such as detectives, crime-scene investigators, coroner’s office personnel, and firefighters, that are deemed necessary. Cordoning off the scene to protect the integrity of any evidence. Detaining and separating any suspects or witnesses whenever possible. Establishing a security log for any and all persons who enter or leave the crime scene.