After the body of Annie Le GRD ’13 was found behind a basement wall in the medical school lab building at 10 Amistad St. and Raymond Clark III, an animal technician in the building, was identified as a “person of interest” in the investigation, commentators inevitably compared the case with the still-unsolved murder of another Yale student, Suzanne Jovin ’99, on Dec. 4, 1998. Many suggested the conduct of the investigation reflected lessons learned from that earlier investigation.

Clark’s arrest last Thursday reflected, first and foremost, the hard work, skill and high degree of professionalism of the investigators and forensic scientists who worked on the case. They were no doubt greatly assisted by the unusual security features of the lab building. In addition to the 75 cameras covering its entrances, entry to the building and the labs within required a magnetized identification card. Computerized records of all swipes were available, disaggregated by person and room. Even before Le’s body was found, investigators knew that after entering the building, she went to a basement lab room, Clark entered the room a short time later, she didn’t swipe into any other lab area, and she didn’t leave the building.

Nevertheless, there were important lessons drawn from the Jovin investigation. As University Vice President and Secretary Linda Lorimer told the New Haven Independent, “A lesson learned was to try to make sure that in the very first days you try to marshal all the expertise you can to solve the crime.” When the Yale Police theorized that Le’s disappearance might have something to do with her imminent marriage and might have involved travel across state lines, the FBI was immediately brought into the case. And even when it was still a missing person case rather than a homicide, the Major Crime Squad of the Connecticut State Police was brought into the investigation.

In marked contrast, in the late evening of Dec. 4, 1998, as soon as he heard about the murder of a young woman in New Haven earlier that evening, Dr. Henry Lee, the eminent forensic scientist who at the time was the head of Connecticut’s Department of Public Safety, the State Police and the State Police Forensic Science Lab, called the New Haven police and offered to send in the state’s forensic experts. The New Haven police inexplicably declined the offer. The State Police Major Crime Squad was never brought into the case. Very little forensic evidence was found, and the little that was found was not analyzed immediately. Most importantly, scrapings from the undersides of Jovin’s fingernails — literally, the very first place one would look for the DNA of the killer of someone who had been stabbed 17 times — were not tested until more than two years later.

In the Le investigation, 300 items were collected from the crime scene and a number were tested immediately for DNA. Within 24 hours of taking a DNA sample from Clark, the state’s forensic scientists had matched his DNA to that found on Le’s clothing, in the area where her body was hidden and on bloody clothing concealed above a ceiling tile. Reportedly, her DNA was found on his clothing.

If there were lessons learned from the Jovin case about how not to organize an investigation, the Le investigation provides an equally important lesson about the need to collect every possible piece of evidence and test all of it for DNA. Applied to the ongoing Jovin investigation, that means conducting every possible test on the existing evidence for DNA and deploying every possible technique to track down the source of the male DNA found in the scrapings taken from her fingernails.

Last week, Thomas and Donna Jovin, Suzanne’s parents, wrote an open letter to Gov. M. Jodi Rell expressing their frustration with delays at the state forensics lab in conducting the tests requested by the team of retired State Police officers that is now investigating their daughter’s murder. Potentially helpful forensic investigations made possible by significant technological advances over the past decade have not yet been carried out because the lab is underfunded and understaffed. The Jovins urged that steps be taken to rectify those shortcomings.

The lab is indeed understaffed. Although the number of profiles in the state’s DNA database has increased dramatically in recent years — there are now 51,000, compared with about 20,000 three years ago — the lab still faces a backlog of some 12,000 profiles that have to be processed. It was absolutely correct that the evidence in the Le investigation be given top priority last week. But the lab should not have sat for months on the request from the investigative team.

No doubt some of the tests — for example, extracting DNA from a smudged palmprint on a soda bottle found at the crime scene that was dusted for fingerprints — are unusually difficult. No doubt some of the techniques — for example, using familial searching to find the source of a rarely-observed sequence of molecules in the DNA found in the fingernail scrapings and analyzing her clothing for possible “touch DNA” left by the killer — are unorthodox and even controversial. But for a cold case that is almost 11 years old, all of them are needed.

David Cameron is a professor of political science.

DAVID CAMERON