Lt. Clyde Cowan used to carry a forensics kit that could fit in his pocket.
Now the equipment fills a van.
“In those days, we had to collect all the evidence ourselves,” said Cowan, commander of the Major Crimes Unit for the Knox County Sheriff’s Office. “We’d spend a lot of time on the crime scene, just checking for prints. Now we can do so much more.”
Ask any veteran homicide detective in East Tennessee, and they’ll say the same. Changes in forensic technology over the past three decades have rewritten the rules of murder investigation, offering ways to solve crimes that old-time detectives never imagined – and creating new problems along the way.
“You had to be a heck of a detective back then to solve cases,” Knox County Sheriff Jimmy “J.J.” Jones said. “Now it’s a whole new ball game.”
That progress came with a price tag, not just in dollars. The same technology that helps crack a whodunit can bog down a smoking-gun case.
William Paul Phillips, 8th Judicial District attorney general, never tries a case without wondering how television would present it.
“When I started trying cases 35 years ago, TV was dominated by Westerns,” said Phillips, whose district covers Union, Claiborne, Campbell, Scott and Fentress counties. “Today it’s crime dramas – ‘CSI,’ ‘Cold Case’ and the rest. Juries today have higher expectations because they see those shows, and some of those things they see on ‘CSI,’ we can’t do.”
Homicide 2.0
Even with the drawbacks, no one’s asking to go back to the old days. Computers and specialized forensic teams make the job easier for everyone in the long run.
“It frees up the detective to do more things, like talk to witnesses,” Cowan said. “When there’s not a lot of forensic evidence, then that’s where the old-school detective comes in.”
Computerized nationwide databases can compare thousands of fingerprints at the click of a mouse – no more thumbing through index cards by hand, poring over loops and whorls for hours with magnifying glasses. Scientists can test a drop of blood found at a crime scene and match it to a single suspect with a probability greater than the world’s population.
“Back in the 1970s, we did A, B, and O blood typing,” said Kelvin Woodby, regional crime lab supervisor for the Tennessee Bureau of Investigation’s Knoxville office. “With today’s DNA tests, it’s you.”
Those tests have helped send the guilty to prison or death row and helped free the innocent. Paul Gregory House, 47, spent 22 years under a death sentence for killing a Union County housewife until DNA evidence helped raise enough questions about the case to win his freedom.
“Most of the time at a trial we’re testifying for the defense as well as the prosecution,” Woodby said.
For law enforcement officers facing the withering questions of a defense attorney, training offers the best armor.
The University of Tennessee Law Enforcement Innovation Center has trained officers from every state except Hawaii and Rhode Island at the National Forensics Academy in Oak Ridge on evidence gathering and preservation. About 2,000 officers annually receive specialized training from the LEIC.
Don Green, executive director of the LEIC, said officers learn how to read the hidden messages of blood splatters, fingerprints, footwear and tire impressions and bullet trajectories. The training also teaches how to master digital photography, collecting skeletal remains and DNA collection and preservation.
In addition to the training in Oak Ridge, the forensic academy sends experts to departments across the nation to conduct 40-hour training classes.
“Physical evidence is driving our investigations,” Green said. “Now we’re overwhelming the laboratories with evidence and telling them to identify a suspect.”
Some evidence talks without a test. Cameras posted everywhere from banks to gas stations to traffic lights can trump eyewitness accounts and help investigators retrace a victim’s last steps or a killer’s getaway.
“Big Brother’s not the only one who’s watching us,” Hamblen County Sheriff Esco Jarnagin said. “You’re hard-pressed in today’s world to do anything in a public area without being on tape somewhere. You can’t do a crime without leaving something behind. To commit the perfect crime nowadays, you’d have to be naked or underwater.”
New heights, new hurdles
The perfect clue can be as elusive as the perfect crime. DNA testing takes time and money – two things often in short supply. Results can be inconclusive.
Fingerprints can be fickle, showing up on some surfaces and not others. Smudges can ruin a print. Good luck if the surface gets wet.
“Sometimes, there’s just nothing there,” Jefferson County Sheriff David Davenport said. “But if you test and don’t get anything, these shade-tree attorneys beat you over the head with it.”
Try explaining that to a jury. Agencies across the country complain of jurors who want forensic guarantees of guilt – no excuses.
“We’ve lost cases because the jury expected more from law enforcement,” said Phillips, the prosecutor. “A jury’s not impressed when an officer testifies he didn’t take fingerprints. Maybe he knew they wouldn’t show up, but the jury sees that as laziness.”
Defense lawyers play up those gaps and ask jurors to consider what police might have missed. So police often test everything, which can lead to investigative overkill.
“Thirty-five years ago, it was not unusual to have a murder trial last two days,” Phillips said. “Today it can easily last two weeks. A homicide case file 35 years ago could easily be one accordion file. Today it’s typically two banker’s boxes, and it can easily be 10 banker’s boxes.
“Murder cases are much more complicated now. They’re much more lengthy and more involved. But I also think the prosecution does a better job than we did 35 years ago. From my perspective as an old-timer, people are better defended today. So it’s actually better for everyone.”