In an opening statement four decades in the making, a Montgomery County prosecutor said Monday that Robert Fisher wanted his ex-girlfriend dead because she was “running her mouth to detectives.”

But Fisher’s attorney cast doubt on that assertion, saying the testimony supporting it — nearly all of it from long-dead witnesses — was unreliable. She urged jurors to acquit Fisher, 75, of first-degree murder in a 1980 shooting for which he had already been convicted and sentenced to death.

After decades of successful appeals, Fisher is on trial for the fourth time in the death of Linda Rowden, 26, who was shot twice as she drove Fisher and another man, Richard Mayo, through Norristown in July 1980.

Through the years, those appeals overturned two convictions and three death sentences because of errors by judges and prosecutors. After Fisher’s second conviction, a federal judge upheld the guilty verdict, but ruled that the death sentence was improper. In 2018, another federal judge overturned both Fisher’s conviction and his third death sentence, setting the stage for this week’s retrial.

Like the previous trials, Monday’s was held in Norristown. But this time, the coronavirus has limited the courtroom capacity; Rowden’s sister and brother-in-law were among the few onlookers allowed to attend.

Prosecutors told the jury Fisher pulled the trigger as he rode in the back seat and argued with Rowden for cooperating with police in an investigation into the death of a man Fisher was suspected of killing.

Multiple witnesses saw the shooting and its direct aftermath, including Mayo, who had a literal “front row seat” to the violence, according to Assistant District Attorney Tanner Beck. All of them testified during the previous trials that Fisher killed Rowden.

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But, in addressing the jury, Beck acknowledged what he called the “elephant in the room”: Those witnesses are unable to testify again, and prosecutors will have to read to the jury transcripts of their previous statements.

“In an ideal world, we’d love to present them to you, so you could hear what they saw straight from them,” Beck said. “Just because they’re not here to tell you themselves doesn’t mean anything they said back then is any less true or less powerful.”

Fisher’s attorney, Carrie Allman, cautioned jurors against relying too heavily on those voices from the past, especially Mayo, whom she described as nothing like the “star witness” prosecutors wanted him to be.

She said he was a heavy heroin user at the time of the shooting, and he initially lied to police, giving them his brother’s name because there was an active warrant for his arrest.

Allman said it was Mayo who fired the fatal shots, and tried to pass the blame onto Fisher.

“If you’re planning to kill someone for ‘running their mouth,’ why are you doing it in daylight?” Allman said, questioning the prosecution narrative. “And why do you bring a witness along?”

Allman also sought to undermine the other witnesses prosecutors will rely on during the trial, including bystanders who didn’t cooperate with police until years later, or who she said had conflicting accounts that changed after pressure from police.

“Lies don’t last, because they are hard to maintain,” Allman said. “The truth stays the same, but a lie changes. And it changes because you have to keep up with it.”

Beck, however, asked jurors to render the same verdict previous juries had reached: guilty.

“At the end of the day, it’s been 41 years, and that’s a long time to wait for justice,” Beck said. “But justice delayed is not justice denied.”