WHITMAN COUNTY, Wash. — A Pullman Police Sergeant is facing a first-degree custodial sexual misconduct charge for allegedly assaulting a WSU student.

49-year-old Sergeant Jerry Daniel Hargraves was arrested Tuesday then released from jail after appearing in court. Court documents give a timeline of the investigation.

In the Press conference with Pullman Police yesterday, Chief Gary Jenkins said six months isn't an unusual amount of time for this type of investigation.

But still, court documents say detectives found Sergeant Hargraves' DNA on the victim's clothing in August and didn't arrest him until two months later.

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The short answer is paperwork. The timeline of events is as follows:

A WSU freshman said she was sexually assaulted by the Pullman officer at the end of March. She then reported it at the beginning of April.

In the following two weeks, investigators swabbed two patrol cars and the victim's clothing for DNA. It was sent to the state crime lab, and two months later, came back with someone's DNA in June.

Then in July, Washington State Patrol got a warrant to sample Hargraves' DNA. And by mid-August it came back as a match.

So why did it take until the end of October for him to be arrested?

State troopers say the lab may have still needed to file paper work and investigators didn't even submit a completed investigation to the prosecutor's office until the end of September.

They tell KREM, investigators have one shot to build an air-tight case, not to mention one against an area police officer.

Once it's submitted to the prosecutor, it can take even longer for them to decide on pursuing criminal charges.

In Hargraves' first appearance, prosecutors said he was arrested out of concern for safety. Hargrave's lawyer argued if there were safety concerns, they would've arrested him sooner.

KREM reached out to Whitman County Prosecutor Denis Tracy for more information on this, but he's out of the office Wednesday.