A military judge has disqualified a Pentagon legal official from participating in the Guantanamo war crimes trial against a former driver for Osama bin Laden, saying he lacks independence.

The judge ruled Friday that the military must appoint a replacement to Air Force Brig. Gen. Thomas Hartmann, the legal adviser to the military tribunals, before next month’s scheduled trial of Salim Hamdan at the U.S. Navy base in Cuba.

A spokesman for Hartmann’s office did not immediately return messages seeking comment on the ruling.

Defense lawyers say Hartmann rushed proceedings in hopes of speedy convictions and sought to improperly influence who was prosecuted, selecting cases based on their potential to sway public opinion of the process.

At an April 28 hearing on the issue, former chief prosecutor Air Force Col. Morris Davis testified that Hartmann had pushed for “sexy” cases that would capture attention.

As legal adviser, Hartmann is charged with providing counsel to the official who makes key decisions such as whether to approve charges against individual detainees.

Prosecutors argued that Hartmann never subjected subordinates to unlawful influence. Under cross-examination, Davis acknowledged he would have brought charges against Hamdan regardless of any outside influence.

Friday’s ruling directly affects only Hamdan’s case, but a civilian attorney for the Yemeni detainee said it raises questions about the validity of charges that Hartmann was involved in preparing against other suspects at Guantanamo.

“The decision makes clear that whatever other rights Mr. Hamdan may be due,” lawyer Andrea Prasow said, “he is certainly entitled to be tried in a system in which no person seeks to influence, whether through command authority or otherwise, the independent judgment” of prosecutors and defense attorneys.

Hamdan is charged with supporting terrorism and faces life in prison if convicted. His trial, scheduled to start in June, would be the first U.S. war crimes trial for a Guantanamo prisoner.