ERIE – Mercyhurst University Professor Dennis Dirkmaat and now-retired FBI Special Agent Michael Hochrein realized the potential for their skills in forensic anthropology and forensic archaeology when they helped state police crack a 1965 cold case that was unsolved for more than 20 years.
The largest fragment of 15-year-old Patricia Desmond’s remains was only about an inch in diameter, Dirkmaat recalled, and was located at the scene of a house fire after it had been bulldozed and overgrown with weeds and grass.
A 2002 article in the Pittsburgh Post-Gazette says what Dirkmaat and other graduate students discovered at the site confirmed Desmond’s gender and approximate age.
Dirkmaat told the Post-Gazette that he and his peers’ theory was that Conrad E. Miller, the last man reportedly seen with Desmond, killed the girl, burned her body and broke up her bones with a shovel before he burned down the house where the remains were found.
Miller was eventually arrested and charged in the Desmond’s death, Post-Gazette archives say, and was sentenced to seven to 14 years in state prison for third-degree murder in 1988. He was released in 2001.
“That sort of set the tone for me, that there was a place for what we do,” said Dirkmaat, chairman of the applied forensic science program at Mercyhurst.
Since that case, Dirkmaat’s experience has grown to an expertise with mass casualties, particularly plane crashes.
‘Bone left behind’
A Portage Area High School graduate, Hochrein attended the University of Pittsburgh as an anthropology major, specializing in archaeology and historical archaeology.
Hochrein and Dirkmaat met when both were studying archaeology at Pitt.
Dirkmaat responded to the 1994 crash of USAir Flight 427 near Pittsburgh, a crash that investigators attributed to a malfunction of one of the plane’s rudders.
At that time, Dirkmaat said research involving DNA was still developing and it was difficult to identify or recover remains of the 132 individuals killed in an impact that “created tremendous fragmentation of the bodies.”
Now, experts are able to identify human remains from the tiniest of fragments, even in fatal crashes or fires.
“It’s never to ash or dust,” Dirkmaat said. “There’s always some parts of the bone left behind. If we find just a small piece of bone that is unburned, that is enough for DNA these days. It is amazing. That alters what we do at the scene.”
Capabilities with DNA had advanced by the time Dirkmaat watched television footage of the terrorist attacks of Sept. 11, 2001.
When he saw that a plane had crashed in Somerset County, Dirkmaat started to prepare his team.
“I told everybody, ‘we’re going to be headed out,’ ” he said.
United Flight 93 crashed around 11 a.m. Sept. 11, and Dirkmaat said he was contacted by Somerset County Coroner Wallace Miller soon after.
“We raced down there, and I was walking onto the scene around 2 o’clock,” Dirkmaat said.
In 2010, a plane crash in Buffalo, New York, led Dirkmaat to a scene in which one individual had not been identified, even after careful excavation and several examinations of the debris found at the crash site.
Through mapping, Dirkmaat and other investigators were able to reconstruct where the major fire occurred at the scene and gather more information that revealed that the last remaining victim had essentially been cremated upon impact.
“That is why we’re valuable to the cops, to the coroners,” he said. “That realm of the outdoor scene is where we excel.”
Beyond bones to context
As a graduate student at the University of Pittsburgh, Dirkmaat became interested in human and animal bones when he had an opportunity to study biological anthropology. That eventually sparked an interest that became his life’s work.
“There was sort of a new field that had started in the ’70s, which was forensic anthropology,” he said.
As he started taking courses and doing research, he found a career path he said “was wide open.”
“As I studied the field, I realized it was almost exclusively focused on the bones,” he said. “But it wasn’t particularly scientific, because everything was out of context.”
Police would often ask how long remains had been here, whether it was homicide or suicide or how the body got there, Dirkmaat said.
While an indoor scene can be a relatively easy environment for documenting details and reconstructing events of a crime or death, “I saw that that wasn’t being done at the outdoor scene,” Dirkmaat said.
“I sort of devoted my career to, not just the bones, but the bones within the context of the outdoor scene,” he said.
Now, Dirkmaat aims to train students in that holistic approach to crime-scene analysis – not just the bones, but providing an interpretation of how and why they got there.
“It’s a bit different than what other programs will do,” he said.
Outside his work with students, Dirkmaat started outreach efforts – including lectures and training for coroners. But he said he soon realized their unpredictable schedules often couldn’t accommodate training sessions.
Eventually, Dirkmaat and Hochrein started HD Forensics, which provides specialized training and short courses in areas, including crime-scene mapping, mass disaster scene reconstruction, forensic archaeology, forensic taphonomy and fatal fire recovery.
On June 10 and 11, Dirkmaat and Hochrein conducted a short course at Mercyhurst that attracted students from the University of Nevada at Reno, Illinois State University and George Mason University.
Hochrein, from Portage, said working the Desmond case also directed his eventual career path.
Digging through the site where Desmond’s remains were eventually located “showed me how I could apply archaeology, which I loved,” Hochrein said.
He ended up as a special agent in the FBI and was located in the St. Louis, Missouri, office for about 15 years.
Hochrein remembers being one of the first special agents showing up with his personal computer.
When the bureau began using surveying equipment – known as the Total Station system – at crime scenes, and as law enforcement began using that process for accident reconstruction, the FBI launched an evidence response team that deployed Hochrein to major cases.
Hochrein was sent to help at scenes in Afghanistan and Cuba, the 2007 collapse of the Interstate 35 bridge in Minneapolis, the 1995 Oklahoma City bombing, the 2001 terrorist attacks on the World Trade Center in New York City and the arrest of Boston Marathon bombing suspect Dzhokhar Tsarnaev in 2013.
Hochrein said the FBI launched a Total Station program around 2000, when he began providing training on using the surveying equipment to map burials and scenes where human remains were discovered.
‘Context’ is crucial
Hochrein has a passion for mapping because the process provides details that expand investigators’ understanding of what occurred.
“You can have the nicest fingerprint on a weapon, you can have a nice bullet hole or bone trauma, but if you don’t have that in the context of where it was, all you have is a nice piece of evidence,” he said.
Hochrein’s goal for each case is to prepare over and above the amount of details he’d want to have if he was returning to the file as a cold case.
From 2003 until his retirement in December 2018, Hochrein opted to come closer to his hometown and was assigned to the Laurel Highlands Resident Agency of the Pittsburgh Field Division in Johnstown and, while there, assisted with investigations of violent crimes, fraud and child pornography.
His help with local cases in Johns-town and the surrounding area has allowed police to see scenes documented in three dimensions, and to have exact measurements and angles of every aspect – from ballistics to blood stains to reconstructing incidents – with Hochrein’s mapping expertise.
“We don’t do this for one side or the other,” Hochrein pointed out, meaning the mapping is precise and could help either exonerate or convict a suspect.
“It’s scientific and objective, if you do it right.”
Hochrein is an adjunct professor at La Roche College, where he teaches classes on crime scene investigation and criminalistics.
He said he works to challenge his students with elaborate props, unrelated weapons and items at mock crime scenes.
“They get to see the logistics and the challenges you run into,” he said. “We try to make it as realistic as possible.”