Lawyers for the man suspected of killing rap icon Tupak Shakur are investigating evidence that could show an alternative cause of death.

Duane "Keffe D" Davis is the only person still alive who was in the vehicle from which shots were fired in Las Vegas, Nevada, on 7 September 1996.

Shakur died from his injuries six days later.

And Davis's lawyers say they have witness information that Shakur was in stable condition after the shooting.

They are consulting medical and forensic experts to evaluate potential alternative causes of death.

Defence lawyers also want to delay next month's trial, saying more time is needed for investigative work to ensure Davis gets a fair trial.

The motion filed on Friday in a Nevada court provides insight into Davis' defence, noting that a private investigator has identified witnesses who can testify that he was not at the scene of the 1996 shooting, nor was he in Las Vegas at the time.

| Duane 'Keffe D' Davis pictured in 2023. Pic: AP

The motion also suggests that someone else may have orchestrated the shooting and that witnesses who could testify on the matter are being interviewed.

The defence team said in a statement that the new developments and the need to interview key witnesses necessitate a delay.

A hearing has been scheduled for Tuesday to discuss the timing of the trial.

"This case involves decades-old allegations, and with every new piece of evidence, it becomes increasingly clear that critical facts have yet to be fully examined," said attorney Carl Arnold.

On the night of the shooting, Shakur was in a BMW being driven by Death Row Records founder Marion "Suge" Knight.

They were waiting at a red light when a white Cadillac pulled up next to them and gunfire erupted.

Davis, an ex-gang leader who is accused of orchestrating Shakur's killing near the Las Vegas Strip, has pleaded not guilty to first-degree murder and has been jailed since his September 2023 arrest.