Anthony Sanborn looks to his attorney Amy Fairfield at the start of his post-conviction review at the Cumberland County Courthouse on Tuesday, Oct. 10, 2017. Credit: Gregory Rec/Portland Press Herald via AP

PORTLAND, Maine — A friend of a 16-year-old girl killed in Maine in 1989 says police ignored his tip that an unidentified man had threatened her the day before because detectives had already homed in on another man, who is now fighting to have his conviction overturned.

[A Mainer convicted of murder in 1992 is back in court. Here’s what you need to know about the case.]

The Portland Press Herald reports Robert Miller testified Thursday that he tried three times to tell detectives he had heard someone threaten to kill Jessica Briggs. He says the lead detective told him they already had their suspect.

Anthony Sanborn was convicted of Briggs’ death and served 27 years in prison until a key witness recanted. He was released on bail this year.

[Former prosecutor in Sanborn case says authorities did not ignore evidence]

A judge began hearing arguments in a post-conviction review earlier this month.

Sanborn’s attorney alleges a long-standing cover-up. Portland police have denied wrongdoing.

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