When evidence analysis needs to be quick, a Rapid DNA system can be the answer. Fewer samples and shorter lag times mean less resources wasted in the end.
There are no shortcuts in criminal investigations, but a new tool is saving time and investigation expenses at law enforcement agencies throughout the country. Rapid DNA instruments—desktop devices that provide sample-to-result analysis of biological evidence in less than two hours—are making a difference in dozens of U.S. jurisdictions by allowing the timely matching of a suspect’s unique DNA profile to crime scene evidence.
“Rapid DNA is used when we have a crime suspect and need the analysis quickly,” said Deputy Chief David Wilson of the Criminal Investigation Division of the Richland County (S.C.) Sheriff’s Department. “Many times the results are back before the interview of the suspect is completed.”
Last summer, Wilson’s department made a same-day arrest of a shooting suspect when blood spatter on the suspect’s clothes was matched to the victim’s DNA using Rapid DNA technology.
Similar stories have hit the news in recent months. In Goodyear, Ariz., police used Rapid DNA to quickly identify an intruder who left biological material at the scene, and in Palm Bay, Fla., police used their Rapid DNA instrument to nab a burglar who had cut himself as he broke into a home.
About the size of an early laser printer, the IntegenX RapidHIT is a miniaturized lab in a box. The desktop device uses a sealed cartridge system that is pre-filled with chemicals that are identical to the ones used in forensic labs, which extract and analyze DNA samples. While many forensic labs see more value in volume, with up to 96 samples being processed at once, that also means that some cases will have to wait. RapidHIT brings the same technology closer to where the crime takes place, allowing the processing of only up to seven samples for evidence with different—related or unrelated—inner cheek (buccal) swabs and other biological material samples. Cartridges containing evidence samples are inserted into the instrument and identification profiles are usually available in roughly 90 minutes. Once a Rapid DNA instrument has generated a DNA profile, it can be matched to an agency’s local or regional arrestee and offender database.
“Being able to identify a perpetrator within two or three hours of an incident—regardless of the backlog in the lab—is very powerful,” said Vince Figarelli, Superintendent of the Scientific Analysis Bureau at the Arizona Department of Public Safety.
Figarelli, who runs the forensic section for Arizona DPS, a statewide agency handling criminal investigations, initiated integration of three Rapid DNA instruments at facilities in Phoenix and Tucson.
“We have had some cases here where the investigating agency could immediately identify a suspect, rather than waiting for samples to be submitted to the lab,” he said.
Agencies generally wait weeks and sometimes months for traditional forensic lab testing and matching of DNA evidence, with violent crimes taking priority and property crimes “taking the backseat,” according to Figarelli.
In a traditional forensic lab setting, DNA profiling is an eight-step process that starts with serology screening and sample preparation, followed by DNA extraction, quantitation, normalization, amplification and detection procedures. In a rush situation, a DNA profile can be returned in 24 hours, but under normal circumstances, that process takes roughly two and a half months at an in-house forensic lab like the one in Richland County.
When the wait for DNA analysis takes a long time, law enforcement may have to release a potentially dangerous suspect, risking harm to the community. Once a result is finally delivered, additional law enforcement resources are required to track and arrest the offender.
Arrests & Exonerations
Producing a DNA profile does not always lead to an arrest or solve a crime, but exonerations count, too.
Capt. Diana Blackledge, who heads support services at the Palm Bay Police Department, described a set of commercial burglaries that recently occurred in her city. Investigators had vehicle information and a description of the perpetrator, which led to the detention of a suspect.
“At one of the burglaries, there was a drop of blood left behind. We had a suspect in custody and were able to develop enough probable cause in our burglary case to get a court order for his DNA,” Blackledge said. “The officer ran it back to the station as soon as he had the sample. And, right there, the instrument was able to tell us in two hours that we didn’t have the right guy. We could have continued watching this guy for weeks and it would have been fruitless, but instead we knew right away that it wasn’t him. And, for me, that’s almost priceless.”
Validation & Training
Putting a new scientific device, such as a Rapid DNA instrument, through its paces with rigorous on-site testing is crucial to the adoption and integration process. Labs must validate their procedures and the accuracy of their instruments according to guidelines set by accreditation bodies. Law enforcement agencies, where officer-operators run the analysis, need to document procedures and accuracy as well, in anticipation of court challenges that may present themselves once the instrument is in the field.
“For validation, you have a prescribed number of certain experiments you have to do to meet quality standards for our accrediting body,” Dr. Gray Amick, DNA Technical Leader and Assistant Lab Director for the Richland County Sheriff’s Department said, referring to the requirements of the American Society of Crime Laboratory Directors/Laboratory Accreditation Board (ASCLD/LAB).
Rapid DNA instruments not located in labs, but put in place specifically for use by sworn officers, do not need to comply with ASCLD/LAB regulations. However, those agencies still spend months comparing Rapid DNA results to labanalyzed DNA profiles to ascertain—and document—the accuracy of the new technology.
At the Palm Bay PD, the instrument was validated according to guidelines established by the FBI Quality Assurance Standards; Blackledge called it an “extra measure.” For training, law enforcement agencies turn to in-house experts as well as vendor resources to develop custom programs for technicians and officer-operators.
In Arizona, Figarelli and his staff developed a 40-hour science-intensive class that gives officers the background they need to understand the highly complex process that takes place just under the surface of the instrument. They also learn how to query their DNA database once a valid profile has been rendered. Arizona DPS put its curriculum together while conducting validation experiments on the instrument and making custom tweaks to their new database software, a run-up that took about nine months.
Calculating Return on Investment
“While I do think that the results speak for themselves, I am actually working on an analysis of the cost-benefit effectiveness of the system that will probably be published later in the year,” Figarelli said. “If you think in terms of investigations, there can be a tremendous amount of expense and officer overtime in keeping track of what I call a ‘hot lead’—a suspect that an investigator feels really strongly about—while they wait the typical two to three days to get a DNA analysis done.”
Instead, with a Rapid DNA instrument, investigators can have the analysis in two to three hours, make a match and immediately make an arrest, rather than wait around for traditional lab results.
“A lot of this is about exoneration,” Blackledge said. “You know, it saves us money if we can eliminate suspects and not have to spend all the resources, all the manpower trying to chase somebody around because we think that they are the suspect of a crime. To me that’s exciting, I want to see criminals go to jail and innocent people get exonerated. That’s what it’s all about.”
Cynthia Wood is a Northern California based freelancer who writes about business and consumer technology. Contact her at [email protected]