Vital to a Strong Criminal Defense: Crime Scene Analysis, Reconstruction & Diagramming

How can Tennessee defense attorneys representing someone charged with a crime ensure they receive all the facts a crime scene reveals?

Hiring a highly experienced crime scene expert – whose services are paid by the Tennessee Administrative Office of the Courts (AOC), Criminal Justice Act (CJA) funding in federal court, or through private funds – is the best way to ensure an independent crime scene analysis. An independent expert evaluates the facts a crime scene truly reveals to help discern whether the charges against a defendant are valid.

That’s because when a crime occurs, a flurry of activity happens. First responders arrive, assess the situation, assist any victims, secure the scene, talk to witnesses, and then call in and relay information to crime scene technicians and detectives. But how many times are integral details slightly lost in translation that may affect the direction of the initial investigation?

“We’ve cleared at least three people of murder charges because of poor police work, not that there was ill intent by the police,” explains Johnny Lawrence of Berry-Waltz Investigations (BWI), a foremost crime scene analysis, reconstruction, diagramming, and blood spatter expert in Tennessee.

“Why does this happen? Because police departments are very, very busy,” Johnny says. “Sometimes there’s miscommunication or evidence is inadvertently moved. And sometimes – based on what they’re told at the scene – detectives follow theories there is no basis in science for.”

Johnny gained his crime scene expertise by being involved in nearly 1,000 homicide investigations in addition to other types of death investigations since 1982. He is a former Nashville Metropolitan Police Department detective and a current private investigator. Johnny’s had extensive training in crime scene investigations and bloodstain patterns during his 39-year career and now provides similar training to lawyers and other independent investigators.

His crime scene knowledge allows him to look at a crime scene – or photographs of a crime scene – in a unique, detailed, comprehensive way that avoids the pitfalls of tunnel vision or contextual bias.

“Anything I see on a scene, I write it down and think about it,” Johnny says. “Then as I go, I see more things and eventually come up with different possible scenarios. I don’t care who told the officer what. I go in and work this with fresh eyes, as a ‘whodunnit,’ and develop different scenarios. You can’t make an immediate determination.”

DNA Evidence

Even if a defendant’s case has DNA evidence associated with it, it’s possible the DNA evidence does not tell the story the criminal allegations claim it does.

Johnny looks at “what DNA collection process they used and how did they avoid the chance for cross-contamination.” His investigation once found a picture of a crime scene technician “holding evidence while wearing a bloody glove and then touching another piece of evidence.”

“That kind of mistake can put people in jail wrongfully,” Johnny says.

Johnny says his experience and research show that “touch-transferred DNA” (such as skin cells) is so sensitive, it could be transferred somewhere in an unusual way and lead to improper allegations. (As an example, see this Forbes article.)

In addition, DNA evidence can be misinterpreted – as Johnny showed during his investigation in Davidson County of a homeless man charged with first-degree murder.

Johnny’s work led prosecutors to retire the case before it went to trial. Johnny’s crime scene and blood spatter investigation showed the victim, a woman, was killed with a bloody 2-by-4 that police did not collect, not a ball-peen hammer that had both the defendant’s DNA and the victim’s DNA on it. “I was able to show the blood fell onto the hammer; it could not have been the murder weapon,” he explains.

Photographic Crime Scene Evidence

In the homeless man’s case, Johnny reviewed 600+ crime scene photographs taken by two different crime scene units. The first unit was replaced by a second due to overtime concerns. Johnny found that both crime scene units did not collaborate or share information. The second unit, for example, wasn’t told that 27 items in the crime scene had been moved.

When criminal defense lawyers take on a defendant’s case, they typically receive digital records containing the case file, including witness statements, crime scene photos, medical examiner’s reports, victim statements, DNA/forensics evidence, etc.

“I go through every photograph and see things most people don’t see,” Johnny says.

“I look at each picture to see if what they’ve written down in the reports is actually right,” Johnny explains. “I look at the strike marks of the bullets, the positioning of the furniture, bloodstains. If a witness says ‘I saw [the defendant] walk out the back door,’ but there are trees there, I ask why did the witness say that? Did they perhaps assume it or overhear it? I look to see what the evidence shows to corroborate a witness’ statement.

“All these reports are being written from the officers’ notes – and everything from the notes is not put into the reports,” Johnny explains. “I tell our attorneys: ‘Request the officer’s notes.’”

Johnny’s highly detailed work led to a client being found not guilty in Shelby County on two first-degree murder charges. His work involved crime scene investigation, reconstruction, and bloodstain pattern interpretation and analysis.

Not every crime scene investigation leads Johnny to discover wrongful charges or misinterpreted evidence, of course.

“On some cases, it is what it is, or it could be something less than what the defendant is charged with,” Johnny says. “In those cases, my findings could soften the blow and get a better deal for our client.”

The Importance of Gathering & Analyzing All Evidence

Johnny’s advice to criminal defense lawyers is to think about all the evidence that may be associated with the case and hire experts to work through the evidence – particularly crime scene, blood spatter and digital evidence – simultaneously.

“The crime scene needs to be worked along with digital evidence,” he says. “We see a lot of cell phone data, security cameras, Ring doorbell cameras, etc., on our cases. When you have a digital forensics expert trying to put together a timeline of events, that’s where your crime scene expert needs to come in and collaborate and work together with them.”

Berry-Waltz Investigations offers comprehensive investigative services, from crime scene analysis/reconstruction and blood spatter interpretation to fact investigations and digital forensics. For more information about Berry-Waltz Investigations, please visit www.berrywaltzprod.wpengine.com, call (615) 646-0860, or fill out a form here.

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