Updated

The judge presiding over the second prosecution of convicted sniper John Allen Muhammad (search) has removed himself from the case after prosecutors claimed he improperly conducted his own investigation into whether Muhammad had been denied a speedy trial.

Circuit Court Judge Jonathan C. Thacher (search), in a letter to prosecutors and defense attorneys made public Tuesday, said he is removing himself from the case even though he believes he did nothing wrong.

"My concerns and obligations are and always have been the orderly administration of justice" and following the Constitution and state laws, Thacher wrote. "As the trial judge I have taken no action that is inconsistent with this position."

But Thacher said he needed to step aside because "the focus has been diverted away from the legal issues in this case, and needs to be redirected to the prosecution of Mr. Muhammad."

Muhammad was already convicted and sentenced to death last year for the Oct. 9, 2002, murder of Dean Harold Meyers (search) in neighboring Prince William County. But Fairfax County prosecutor Robert F. Horan Jr. has said he wants a second conviction in case the first is overturned on appeal.

It was unclear whether Thacher's decision would further delay Muhammad's trial, which had originally been scheduled for October but was pushed back to January after Muhammad agreed to a limited waiver of his speedy trial rights.

Thacher was investigating the defense claim that Muhammad had been denied a speedy trial when he visited the Prince William jail on Sept. 7 to retrieve paperwork. Prosecutors said Thacher violated his impartiality and improperly discussed the issue with jail personnel who could be called to testify.

In a filing last week, prosecutors said Thacher went so far as to accuse jail personnel or others of altering Muhammad's file and suggested an internal affairs investigation. Some jail workers have since hired lawyers and are no longer cooperating with prosecutors, wrote Deputy Commonwealth's Attorney Raymond Morrogh.

But defense lawyers said prosecutors exaggerated the significance of Thacher's conversations with jail workers, and that Thacher visited the jail because prosecutors failed to provide documents he specifically requested from them.

The speedy trial claim is based on a Virginia law that grants Muhammad the right to trial within five months of his arrest. The question revolves around when Muhammad was arrested for Franklin's killing; prosecutors and defense lawyers disagree on the facts.

Wednesday's evidentiary hearing will go on as scheduled with a new judge, M. Langhorne Keith.

If a judge agrees that Muhammad has been denied a speedy trial, Fairfax County will be permanently barred from putting Muhammad on trial for the killing of FBI analyst Linda Franklin, one of 10 killings in the Washington area over a three-week span in October 2002.

Muhammad's teenage accomplice, Lee Boyd Malvo, was convicted last year in the Franklin killing and sentenced to life in prison.