Michael Usry, a young New Orleans filmmaker, has a flair for the macabre. His award-winning output includes titles like “Murderabilia,” a dark production that spotlights the trade in collectibles related to real-life killings and other violent crimes.

Usry’s work can come off as gratuitously violent, as in a clip from the short film “Winding Down” in which his protagonist disembowels a corpse in a basement.

But for the Idaho Falls Police Department, his filmography seemed outright suspicious.

The authorities in that Idaho city targeted Usry last year as a suspect in the 1996 murder of Angie Dodge, a case that’s drawn national media attention amid claims that the wrong man was convicted.

The fatal stabbing remains steeped in mystery, as DNA from the crime scene failed to match any of the millions of genetic profiles on file in the national criminal database. Police still believe Dodge had multiple attackers, but traditional forensic testing has failed to identify the man whose semen was found on the 18-year-old’s body.

Investigators last year turned to a controversial technique known as familial searching, which seeks to identify the last name of potential suspects through a DNA analysis focusing on the Y chromosome. A promising “partial match” emerged between the semen sample and the genetic profile of Usry’s father, Michael Usry Sr. — a finding that excluded the father but strongly suggested one of his relatives had a hand in the young woman’s murder.

The results instantly breathed new life into a high-profile investigation in which Idaho Falls authorities have weathered intense criticism. But the story of how the police came to suspect the younger Usry and then eventually clear him of murder raises troubling questions about civil liberties amid the explosive — and increasingly commercial — growth of DNA testing.

The elder Usry, who lives outside Jackson, Mississippi, said his DNA entered the equation through a project, sponsored years ago by the Mormon church, in which members gave DNA samples to the Sorenson Molecular Genealogy Foundation, a nonprofit whose forensic assets have been acquired by Ancestry.com, the world’s largest for-profit genealogy company.

Ancestry.com received a court order last summer requiring it to reveal Usry’s name to the police, although it is listed as “protected” in the Sorenson Y-chromosome database, according to court records obtained by The New Orleans Advocate. Following this new lead, the police mapped out five generations of Usry’s family, narrowing their focus to three men.

Only one, the New Orleans filmmaker, fit the mold of a plausible suspect, according to an application for a search warrant. Usry, 36, had ties to Idaho, including two sisters who attended a private university about 25 miles from the crime scene.

In addition, some of Usry’s Facebook friends lived in the state. And in their search warrant application, police also mentioned Usry’s short films, which they said generally have “dealt with some sort of homicide or killings.”

“All of the circumstantial evidence was right,” said Sgt. James Hoffman, of the Idaho Falls Police Department. “He seemed like a really good candidate. But we’ve had that happen before.”

Days of suspense

Detectives traveled to New Orleans in December and persuaded a magistrate judge to sign a search warrant ordering Usry to provide his DNA for comparison. For about a month, Usry lived in a state of suspense, fearing he’d be taken into custody regardless of the test results.

“I had lots of days sitting at the house with the dog,” he recalled in an interview, “wondering if these guys were going to use a battering ram to bust open the door and shoot my dog after he started barking at them.”

On. Jan. 13, Usry received the email he’d been awaiting. His DNA, Hoffman wrote, did not match the semen from the scene of Dodge’s murder.

“It turned out to be nothing,” Hoffman said in a telephone interview. “I wish it wasn’t a dead end, but it was.”

Several experts agreed the Idaho Falls police had probable cause to take a swab from Usry. But his experience touches on the delicate balance between the right to privacy and public safety.

“It’s not very common to see this sort of thing, and I frankly hope it doesn’t become very common because an awful lot of people won’t bother testing” their DNA, said Judy G. Russell, a genealogist and attorney who writes The Legal Genealogist blog.

Ancestry.com did not respond to questions about how frequently it receives court orders in criminal investigations and whether it ever resists law enforcement requests to learn the identity of otherwise protected genetic information.

Erin Murphy, a professor at the New York University School of Law who has written about familial searching, said Usry’s case is the first she’s seen in which law enforcement used a publicly accessible database like Sorenson, as opposed to a private law enforcement database, to obtain an investigative lead.

“I think what we’re looking at is a series of totally reasonable steps by law enforcement,” Murphy said. “But it has this really Orwellian state feeling to it, and it is a huge indictment of private genetic testing companies and the degree to which people seamlessly share that information online.”

A controversial tool

Familial searching differs from traditional DNA testing, a mainstream tool used to identify criminals. In familial searching, the number of partial matches — in which genetic profiles share several common “alleles,” or variant forms of genes — can be overwhelming.

In Usry’s case, Hoffman’s search of the Sorenson database yielded 41 partial matches. Though the name was initially shielded, the strongest match was Usry’s father, with 34 of 35 alleles, which the Sorenson Forensics Lab in Utah deemed “exceptionally good” and indicative of a close family relation to the suspect.

Familial searching in law enforcement dates back over a decade to Great Britain, which employed the technique in the 2003 case of Craig Harman, who threw a brick through the windshield of a passing vehicle, causing the driver to suffer a fatal heart attack. British authorities could find no direct match between the DNA found on the brick — Harman’s blood — and a national database of criminal defendants.

But they found two dozen similar genetic profiles belonging to people from the surrounding region, including Harman’s brother, who represented the closest partial match to the blood sample. Further probing led investigators to Harman, who reportedly gave his DNA and confessed to the crime in the face of a match.

In the United States, the most notable use of familial searching was the case of the notorious Grim Sleeper. An alleged serial killer, Lonnie Franklin, was indicted in 2011 on 10 counts of murder in Los Angeles after authorities found similarities between crime scene evidence and the DNA of Franklin’s son, who recently had been jailed on a weapons charge.

The public debate largely has centered on the use of law enforcement databases like the FBI’s Combined DNA Index System.

Proponents argue familial searching is a harmless way for police to crack otherwise unsolvable cases. The closest partial matches can steer investigators toward a criminal’s family members, whose DNA profiles closely resemble those of a convicted or incarcerated relative.

Skeptics like Murphy, the NYU law professor, warn that the technique drastically expands DNA testing beyond the function envisioned by states that compel criminal defendants to submit DNA samples upon arrest. Many states lack formal legal rules governing the use of familial searching by law enforcement, while Maryland has explicitly outlawed the practice.

In Louisiana, familial searching by law enforcement appears to be exceedingly rare. The Louisiana State Police Crime Lab does not conduct that method of testing, said Capt. Doug Cain, a State Police spokesman.

“It’s not been a bone of contention here as it has in other states,” said Kevin Ardoin, director of the Acadiana Crime Lab. “I don’t believe we have any restrictions on it, though, probably because it’s not been pursued or challenged.”

Usry’s experience, Murphy noted, differs from a familial search involving a law enforcement database, in that Usry’s father voluntarily submitted his DNA as part of a genealogical project. But, she added, “that doesn’t mean that many people wouldn’t find it surprising — and troubling — to know that a DNA swab they sent in for recreational purposes” could years later land their child in an interrogation room.

“I think this case puts into stark relief some of the critical privacy concerns surrounding consumer genetic testing companies, public repositories of genetic information, DNA familial search practices and the general degree to which law enforcement should be able to access genetic information,” Murphy said.

A cloud of suspicion

The call came in early December, as Usry was visiting his parents in Mississippi. The caller identified himself as a law enforcement official in New Orleans and said he was investigating a hit-and-run in City Park.

“I didn’t take it as a big deal,” Usry said. “He said he wanted to get together, ask a couple of questions and take a couple pictures of my car.”

Knowing he had nothing to hide, Usry agreed to meet with the officer. After he returned to New Orleans, three lawmen arrived at his door, including two detectives from Idaho Falls. The other, Usry said, was a federal agent.

The officers led Usry to the 13th floor “of some building by the Superdome, an interrogation room with a one-way mirror.”

“They told me that it was not, in fact, about a hit-and-run,” Usry said. “They wanted to know about my travels to Idaho.”

Usry piqued the officers’ interest, he said, when he recounted a ski trip he’d taken when he was about 19 with three friends. While Usry couldn’t recall ever setting foot in Idaho Falls, his interrogators determined he must have passed through the city when driving to Rexburg, Idaho, to pick up a friend.

At the end of the interview, Usry said, the federal agent entered the small room with “gloves on, ready to go.” It finally occurred to him that he might want to consult a lawyer when the lawmen hovered over him and extended a long Q-tip into his mouth.

“It really took me until almost the end of the entire experience to realize that they were saying, ‘We think that you, Michael Usry, are a suspect in this murder,’ ” he said.

When the officers dropped Usry off at home, he said, “I just kind of stood on my sidewalk dazed for a few minutes.”

He called a friend, a co-producer of the short film “Murderabilia.”

“You’re not going to believe what just happened to me,” Usry told him.

It took his friend about 30 seconds to search “Idaho Falls cold case murder” online and determine the interrogation was related to the Dodge killing, he said.

Coming to terms

In the weeks since the questioning, Usry said, he’s wondered whether someone else in his family — perhaps a cousin or distant relative he hasn’t even met — had something to do with the killing.

Colleen M. Fitzpatrick, a well-known forensic genealogist, said a partial match of 34 of 35 alleles is “very close to a 100 percent” indication that the donor of the semen is an Usry. She suggested the authorities take a closer look at the family lineage.

“There’s still a small percent chance that it’s not an Usry due to an adoption or illegitimate” child in the family lineage, she noted.

Greg Hampikian, a professor at Boise State University who has worked on the Dodge case, also seemed impressed by the partial match. According to the search warrant application, he told police that Usry’s father “would probably be within three or four generations” of the unidentified suspect.

Asked whether police thought the semen donor might be someone else in Usry’s family, Hoffman, the Idaho Falls sergeant, said, “Not that I can see so far. We’re still investigating everything we can.”

Usry said he regarded his experience as an invasion of privacy, made even worse because his father’s DNA had been submitted during a church-sponsored event. But it also has emboldened Usry to try to find out the truth about the Dodge case — in the best way he knows how.

He is working on a documentary and researching the well-publicized case of Christopher Tapp, whose conviction in Dodge’s killing has drawn widespread criticism.

“I feel a connection to this case because I’ve been forced to be involved in it,” Usry said. “The guy that really killed Angie Dodge deserves to be put in jail.”

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