DELPHI, Ind. – Why now?

That’s one of the biggest questions surrounding the arrest of Richard Allen, who’s charged with murdering Abby Williams and Libby German in February 2017.

It appears a “clerical error” may be to blame.

The investigation has been ongoing for more than five years. And while police have released pieces of evidence, including a pair of sketches, an audio recording and a grainy photo of the killer, they didn’t arrest Allen until late October 2022.

delphi murders suspect richard allen
Booking photo of Richard Allen

We’ve since learned that investigators actually interviewed Allen in 2017. He told them he’d been on Monon High Bridge and the Freedom Bridge between 1:30 p.m. and 3:30 p.m. on the day of the murders. The timing matched the window in which the girls died.

It appears that information had been essentially lost.

Both an investigative source and The Murder Sheet Podcast said the 2017 interview with Allen was overlooked due to a “clerical error.”

Someone mislabeled or misfiled tip information in the system, which means it didn’t show up in the correct location during a data search. The FBI says its review of the matter showed that FBI employees correctly followed established procedures.

Abby Libby Delphi investigation
Abby Williams and Libby German/Provided by families

As the case stalled, police went back to the very beginning of the investigation. That’s when they discovered the interview with Allen that prompted them to take a closer look.

Indiana State Police announced his arrest on Monday, Oct. 31, although FOX59 learned about the arrest the preceding Friday. His potential tie to the case remained under seal until Nov. 29, when a judge released a redacted version of the probable cause affidavit.

Court documents said an unspent round from a gun owned by Allen tied him to the murders of Abby Williams and Libby German. Investigators discovered the bullet just feet away from the girls’ bodies.

Allen told police he’d never let anyone else use the weapon, a SIG Sauer P226. A laboratory analysis determined that the unspent round had been cycled through Allen’s gun, according to court documents. Allen was unable to explain how it got there.

Grainy image released in February 2017 of the Delphi killer/Indiana State Police

Based on that information and eyewitness accounts, police believe Allen is the man seen on a video taken by Libby German, according to court documents. Police had released a grainy photo of the man, commonly known as “Bridge Guy,” in 2017.

For now, Allen remains in custody. A bail hearing is scheduled for February 2023.