According to new "witnesses" there was another guy in Mumia's brother's car who was the real shooter, but the brother never said this or named this phantom.

"At the post-conviction review hearings, new witnesses were called. William "Dales" Singletary testified that he saw the shooting and that the gunman was the passenger in Cook's car."

"Singletary's account contained discrepancies which rendered it "not credible" in the opinion of the court."

"The six judges of the Supreme Court of Pennsylvania ruled unanimously that all issues raised by Abu-Jamal, including the claim of ineffective assistance of counsel, were without merit."

https://murderpedia.org/male.A/a/abu-jamal.htm