Opinion: Forensic Science under the Magnifying Glass

Contributed by David Howitt and Fred Tulleners, Forensic Science Program

Earlier this year, the National Research Council, part of the National Academies of Science, released its eagerly-awaited report on the practice of forensic science in the United States. Judging from some headlines, one might think that forensic science is unreliable, but this is far from the case. In fact, the report does make constructive suggestions for strengthening forensic science: more basic research, improved standards and accreditation, and promoting the independence of crime labs.

Octopuses prefer HDTV

At last a reason to buy a High-Definition TV: your octopus will enjoy it. Researcher Renata Pronk at Macquarie University in Sydney, OctopusAustralia has been using HD screens to study octopus behavior. Apparently the octopus eye is so sophisticated that standard definition video, at 24 frames per second, would look like a series of stills to them.

Pronk found that the octopus in the lab would try and attack a video of a crab (their favorite food). Shown a video of another octopus, they would either become aggressive or try to hide. They seemed uninterested in an unfamiliar object (a bottle on a string).

Jeff Mount on New Orleans’ levees

Interviewed by ABC-7 yesterday UC Davis geology professor and flood expert Jeff Mount commented on the state of the levees in New Orleans and in our region. Levees are meant to take a certain amount of “overtopping” where water flows over the top, and even to spring a few leaks without failing, he said. Tested by Hurricane Gustav, the rebuilt levees of New Orleans are doing what they are supposed to do, Mount said.

But the levees still need strengthening.

“Had this been Katrina, we would’ve seen flooding again in New Orleans… exactly the same,” said Mount.

Firearms Microstamping Feasible but Variable

New technology to link cartridge cases to guns by engraving microscopic codes on the firing pin is feasible, but did not work equally well for all guns and ammunition tested in a pilot study by researchers from the forensic science program at the University of California, Davis. More testing in a wider range of firearms is needed, the researchers said. A copy of the report can be found here.

Using DNA to trace people, past and present

Two stories in the news this week show how DNA analysis revolutionized our ability to identify people and trace their ancestry.

In Thursday’s New York Times, Amy Harmon reported on how police are using “surreptitious collection” of DNA samples to catch a suspect. A soda can offered during an interview; a dropped cigarette butt; even a drop of saliva from a suspect in the street, can provide enough DNA to link a suspect to a crime. In some cases, detectives have even used a ruse such as sending a suspect an invitation to join a class-action lawsuit so he would lick an envelope and return it to them.

NRC Advises Against National Ballistics Database

The National Research Council, part of the National Academies of Science, released a report yesterday advising against setting up a national database containing images of ballistics markings from new and imported guns sold in the U.S.

The idea behind such a database would be to link bullets from crime scenes to specific guns. But the NRC expert panel found that searches of the database would produce too many “false positive” results to be useful.

The full report is available online here.

Disarming the prohibited

State officials have been seizing an increasing number of firearms from people prohibited from owning them under state or federal law, according to the Contra Costa Times. The stepped-up enforcement follows introduction of a computer system, the Armed and Prohibited Persons System, that matches gun ownership records with records of people banned from owning guns because of criminal convictions, restraining orders or mental health problems, among other things.

UC Davis physician Garen Wintemute has been advising the state on implementation of the system.

Schwarzenegger signs microstamping bill

Governor Schwarzenegger signed 101 bills into law and vetoed 58 Saturday. One of them was a bill requiring that some handguns be fitted with technology that etches or “microstamps” a code into the cartridge each time the gun is fired.

Researchers from the UC Davis Forensic Science Program tested a version of this technology. They found that while it worked well for some guns, it did not work equally well for all the guns and ammo they tested. The study is currently being reviewed by the sponsors, the California Policy Research Center, but was the basis for the Master’s thesis for graduate student Mike Beddow, who did most of the experimental work under the direction of Fred Tulleners.

More insect expertise needed, and not just for solving murders

Recently, Lynn Kimsey of the UC Davis Bohart Museum of Entomology testified in the trial of a man accused of killing his family. He’d set up an alibi by flying to Ohio on business, renting a car and driving back to California to carry out the murders, then driving back to Ohio. Kimsey helped break his alibi by showing that the insects stuck in the car’s radiator grille included some only found in the West.

The story received wide media coverage.

But there is a problem, Kimsey writes in an op-ed in the LA Times:

Dog DNA evidence in Atlanta killings

The Atlanta District Attorney and lawyers for convicted killer Wayne Williams are arguing over a new analysis of DNA evidence by UC Davis scientists. The evidence in question is from dog hairs found at the murder scene, which appear to match Williams’ dog.

Williams was convicted in 1982 of two murders and is thought to have committed another 22. Earlier this year, a judge ordered new tests — not available in 1982 — on evidence collected in the case. Most of the testing is being carried out by FBI labs, but the Veterinary Genetics Lab at UC Davis was asked to test the dog hair for a DNA match.