When Fort Wayne police Detective Brian Martin arrived last July at a Grabill trailer park home, he was there to capture a man who in just hours would become northeast Indiana’s most notorious criminal suspect.

The veteran investigator left 13722 Main St., lot No. 4, in the early-morning hours of July 15 with John D. Miller.

A former Walmart employee, Miller, 60, is now Indiana Department of Correction inmate No. 264854 at the prison in New Castle and perhaps the area’s most well-known killer. He admitted in December to the sexual assault and murder of 8-year-old April Tinsley 30 years before.

For Martin, the July 15, 2018, arrest capped a case that began in 1988 and remained unsolved for a generation. But it also kick-started a series of events in which he and other investigators would be asked to explain what led police to Miller’s doorstep. In addition, investigators would be asked to help law enforcement agencies use similar efforts to nab suspects in other cold cases.

Since the arrest and Miller’s guilty plea, Martin has attended six conferences around the country to outline how DNA and publicly available genealogy data can be used to identify criminals. He’ll attend six more by the end of the year, and two already are scheduled for 2020. 

Martin also has spoken by phone to agencies in Canada, Israel and England about the novel investigative techniques.

“It’s kind of been a whirlwind,” he said last week.

April Tinsley vanished April 1, 1988 – Good Friday – from her neighborhood on Fort Wayne’s south side. Her body was found days later in a ditch in DeKalb County.

Despite DNA evidence collected there and notes left years later by the alleged killer taunting police, investigators were never close to finding the suspect – until last year.

In May 2018, Martin contacted Parabon Nanolabs, a Virginia company working in the growing field of “next generation forensic and therapeutic products by leveraging the enormous power of DNA,” according to its website. Weeks later, using DNA provided by local investigators and research from celebrity genealogist CeCe Moore, Parabon narrowed suspects in the case to Miller and his brother, identified in court documents as JPM.

Evidence recovered from Miller’s home later excluded JPM as a suspect.

“It’s been amazing,” Martin said, referring to the technology. “The doors it’s opened for us is amazing.”

The DNA profile was uploaded to GEDmatch, a website that allows users to submit their profiles and find relatives by comparing genetic codes. Martin said the method has been used in one other local case but would not provide specifics.

Moore, genealogist for the PBS show “Finding Your Roots with Henry Louis Gates Jr.,” crunched the data and found Miller and his brother.

The method has been used to catch other suspected killers including Joseph James DeAngelo, the alleged Golden State Killer accused of more than a dozen murders and 50 rapes in California in the 1970s and 1980s.

It’s been hailed by police and Moore as “a game-changer,” and it has raised the profile of investigators like Martin who typically work behind the scenes to conduct interviews and pore over evidence to solve crimes.

“We don’t say much (in) public when we’re doing a criminal case,” Indiana State Police Capt. Kevin Smith said.

He joined the state police in 1987 and was assigned to April’s case in 2005. He appeared in March on an episode of the Indianapolis true crime podcast Crime Junkie, joining several other investigators to sit for interviews about the case.

Smith said he also has been asked by other law enforcement agencies to share information about DNA and genetic genealogy.

“This is a big deal,” he said. “Once I figured out the power this particular investigative tool had, I immediately began training our people.”

Miller signed a plea agreement calling for him to spend 80 years behind bars, and he will likely die in prison. His lawyer, Anthony Churchward, said he hasn’t heard from Miller since a Dec. 21 sentencing hearing in Allen Superior Court.

April’s mother, Janet Tinsley, said the year that has passed since her daughter’s killer was finally captured moved quickly. She’s not going to celebrate the anniversary, though she said she might visit April’s Garden – the memorial for the girl at Hoagland and Masterson avenues.

Janet Tinsley said strangers have largely stopped asking about the case when she’s in public.

“It’s getting a little bit easier,” she said.

mleblanc@jg.net