Despite an effort to portray two key prosecution witnesses as habitual liars, a jury on Thursday found Bryan Lamar Lee guilty of murder.

Lee, 22, was on trial before Pima County Superior Court Judge Javier Chon-Lopez on charges of first-degree murder, aggravated robbery and kidnapping in the 2011 killing of Jordan Peterson.

He was found guilty of first-degree murder and kidnapping. He was acquitted of aggravated robbery.

Another man, Reed Marrone pleaded guilty to first-degree murder . He is serving 25 years to life in prison.

At trial,the state argued that Lee and Marrone killed Peterson and stole marijuana from him to avoid paying a drug debt Marrone owed him.

The state’s two key witnesses both testified to excessive drug use, which the defense attempted to use to impugn their credibility.

During cross-examination, defense attorney Joel Feinman questioned Tyler Brown, 20, about the numerous lies he told police and investigators in the years and months prior to the trial.

Brown testified that he helped Lee and Marrone drive Peterson’s body to Marana and bury it in a shallow grave.

Feinman argued the state had relied on the statements of an admitted liar to implicate Lee in the murder.

He showed at least 20 lies and misstatements Brown eventually admitted to making, some of which appeared aimed to mitigate Brown’s involvement and others suggesting he had no knowledge of Peterson’s disappearance and murder.

The defense argued Lee only helped get rid of Peterson’s body but did not kill him.

Deputy Pima County Attorney Victoria Otto told jurors in closing arguments Wednesday that Brown had changed his lifestyle in the years since Peterson’s death, leaving the world of crime and drug abuse behind.

Brown also said a baby he and his girlfriend are expecting has helped to change his perspective.

The defense attacked the credibility of another witness for the prosecution, Kayla Becwar, who was Lee’s girlfriend at the time of the killing.

Becwar, 20, reported the murder to police after Lee confessed the killing to her.

In her testimony, Becwar said Lee described in great detail how he and Marrone planned to kill Peterson.

She said they called Peterson to Marrone’s apartment on the promise they would pay him several thousand dollars Marrone owed. When Peterson arrived, she said, Lee and Marrone attacked him and strangled him.

Feinman questioned Becwar’s memory, noting she was a habitual opiate and marijuana user at the time.

He also suggested a $25,000 reward offered for information about the case motivated her to turn Lee over to the police.

Otto argued Becwar had sought the reward only after police told her she might be eligible to claim it, though it was long after she had already told them about the murder.

Contact reporter Patrick McNamara at 573-4241 or On Twitter @pm929.