A US military judge has disqualified the Pentagon’s top legal adviser in the Office of Military Commissions, one of the key figures in Guantanamo war crimes tribunals, The New York Times reported.

Navy Capt. Keith Allred ruled that Brig. Gen. Thomas Hartmann of the Air Force Reserve was too closely allied with the prosecution. He is supposed to be a neutral adviser to the official directing the commissions. The military must appoint a replacement before next month’s scheduled trial to Salim Hamdan at the US Navy Base in Cuba.

Allred found that Hartman pressured prosecutors to present certain cases because they were “sexy;” he suggested that factors other than case’s merits “were at play,” the New York Times reported. He also tried to influence the professional judgement of the prosecutors.

Cmdr. J.D. Gordon, a Pentagon spokesman, did not return messages seeking comment on the ruling, saying defence officials are still reviewing the ruling, the newspaper reported.

The trial against the detainee, Salim Ahmed Hamdan, was scheduled to begin next month. He is charged with supporting terrorism and faces life in prison if convicted.

“National attention focused on this dispute has seriously called into question the legal adviser's ability to continue to perform his duties in a neutral and objective manner,” Allred wrote on Friday, according to a copy of the ruling, saying he could not find that Hartmann “retains the required independence from the prosecution.”

Military defense lawyers told the Times they expected the issue would affect other cases and possibly delay prosecutions, including the death-penalty cases of six detainees at Guantanamo Bay, Cuba, for the Sept. 11 attacks.

Hamdan’s trial would be the first US war crimes trial for a Guantanamo detainee.