FAIRBANKS—On Friday, Marvin Roberts became the fourth and final of the so-called Fairbanks Four to take the witness stand to both proclaim his innocence and submit to an hours-long public cross-examination.

His testimony also marked a dividing line in this month-long hearing for the four men convicted of the 1997 murder of Fairbanks teenager John Hartman.

After Roberts finishes his testimony on Monday, his side will rest its case and pass the podium to the state of Alaska's attorneys who are working to reaffirm the murder convictions. Among the witnesses they plan to call is Aaron Ring, the former Fairbanks police detective who led the original Hartman murder investigation.

Roberts wore a turquoise shirt and moose-hide vest with two eagle designs in court Friday. He was paroled this summer and has sat next to his attorney at most of the hearing. His is co-petitioners — George Frese, Kevin Pease and Eugene Vent —remain in jail, serving sentences that range from 39 to 79 years. They've listened to the hearing over the phone each day.

Roberts started his testimony by explaining he has spent 17 1/2 years in jail moving among 13 correctional facilities in Alaska, Arizona and Colorado. He remains under the supervision of the Alaska Department of Corrections until his parole ends in 2031 — if this lawsuit doesn't achieve its goal of ordering the immediate release of all four men.

During the first 19 years of his life before his arrest he lived in Fairbanks and in Tanana. He worked as wildland fighter and a Riverboat Discovery tour guide among his jobs. A few months before his arrest he was valedictorian of Howard Luke Academy, a small alternative high school in West Fairbanks.

Busy night

Unlike his three co-petitioners, Roberts had a car on his last free Friday night. As a social teenager with wheels, his alibi narrative is the most complex.

The account he gave in court Friday took him across town several times Oct. 10 and 11 as he oscillated between a wedding reception at the Eagles Hall on First Avenue, a Mapco gas station, various nightclubs and the homes of several friends.

Also unlike his co-petitioners, Roberts says he wasn't drinking alcohol that night. Only he and Pease have said they lack any alcohol-induced blackouts from that night and can account for their location the entire time in question. Roberts said he was smoking pot, something he did almost every day in 1997.

On cross-examination, Roberts took persistent questions about alcohol from Assistant Attorney General Adrienne Bachman, one of three state attorneys working to uphold the convictions. Bachman asked him repeatedly whether he was drinking, what kind of alcohol he was drinking, and why he answered "yea" instead of contradicting when a police officer in an interrogation assumed he had been drinking.

Roberts said he first learned about Hartman, the teenager who had been found badly beaten near the corner of 9th Avenue and Barnette Street when police came to his home to question him.

They took him to the police station and were soon telling him his car had been spotted at the crime scene. Roberts said he never imagined the police were lying to him. He began trying to imagine a scenario in which his car was stolen, used in the crime, then returned to its parking spot, he said. Then the police began telling him they knew he was involved in the deadly assault.

"I took what they said at full value, up until when they started accusing me of doing violent things," he said. "That’s when I knew they were lying to me. I kept saying I’m innocent, I wasn’t there."

Roberts said he has never wavered in asserting his innocence since the moment the police first came to his house 18 years ago.

Intimidation conspiracy

Bachman hinted at some of the arguments the state plans to use in its case as she cross-examined Roberts.

One argument is that Roberts and his co-defendants intentionally intimidated Arlo Olson, a key witness in the original murder trials. Olson has waffled over the years in the assertion he made confidently before three juries in 1999 that he saw all four plaintiffs together beating and robbing a man named Franklin Dayton on the night Hartman was assaulted. The four were convicted of both Dayton's assault and Hartman's murder.

In his most recent testimony, heard in this hearing two weeks ago, Olson said his eyewitness testimony was heavily coached by Ring, the Fairbanks police detective.

Olson has been in and out of jail on his own problems over the years. Bachman said Friday that she will show in her case that intimidation from other inmates in jail pressured Olson to recant his earlier testimony. The petitioners didn't do the intimidating themselves but encouraged others to do it, she said. She has asked a few witnesses about a jail gang known as the Native Brotherhood, usually over objections from the petitioners’ attorneys.

On Friday, Roberts told Bachman he knew about 10 members of the Native Brotherhood. Bachman also asked Roberts if his co-petitioners were members of the gang, but Superior Court Judge Paul Lyle interrupted this line of questioning after Roberts' attorney objected to the relevance of the question.

"(I don't know) if any particular member of this defendant group engaged in personal acts of intimidation. I don't think they would have been allowed to be housed in the same unit as Mr. Olson," Bachman said in response. "But Mr. Olson was nonetheless intimidated, nonetheless assaulted, nonetheless spit on."

Bachman argued Roberts influenced others outside the prison. She cross-examined Roberts about his jailhouse correspondence, in particular from two advocates of Roberts who the state plans to call as witnesses: Brian O'Donoghue, a University of Alaska Fairbanks journalism professor and former News-Miner reporter who's written extensively about this case, and April Monroe Frick, a real estate agent and advocate who maintains the Free the Fairbanks Four blog and social media campaign.

Bachman asked Roberts if he gave his advocates permission to advance his cause in "whatever fashion," in particular intimidating witnesses.

"I don't endorse that," Roberts said.

The hearing continues at 8:30 a.m. Monday with testimony from Roberts.

Contact outdoors editor Sam Friedman at 459-7545. Follow him on Twitter: @FDNMoutdoors.