(CNN) -- The U.S. government has asked a military appeals court to deny accused Fort Hood shooter Maj. Nidal Hasan's request to keep a beard he has grown and to reject his bid to have the judge overseeing his court martial removed from the case.
Army regulations prevent most soldiers from wearing facial hair while in uniform. Hasan, a practicing Muslim, maintains he has the right to wear the beard under federal law protecting religious rights.
Involuntarily shaving a person is "not a novel concept" and is within the court's rights, the Appellate Government Counsel of the Judge Advocate General's office wrote in a brief for the U.S. Court of Appeals for the Armed Forces.
Hasan did not prove that wearing his beard was "based on a sincerely held religious belief," the filing said.
The brief also raised the concern that Hasan's decision to grow a beard was to make it difficult for witnesses to identify him, calling the timing "questionable."
"In light of the pictures portraying (Hasan) at the time of the offense and presently with a beard, there is no question that his appearance is dramatically different than at the time of the offenses," the government said.
Separately, the filing argued that the judge overseeing the trial, Col. Gregory Gross, is not biased against Hasan, despite defense claims, and that Gross did not interpret Hasan's refusal to shave his beard as a personal attack.
"He is not personally offended about (Hasan) growing the beard," the court document said.
Hasan's lawyers have sought to have Gross removed from the case.
The U.S. Court of Appeals for the Armed Forces postponed the court martial of Hasan, the Army psychiatrist charged with 13 counts of murder in connection with the November 2009 shooting spree at Fort Hood, the sprawling Army post in central Texas.
The move came after his attorneys lost an appeal that upheld the trial judge's order that Hasan appear in court clean shaven. Until this appeal is resolved, the court martial trial remains on hold.
The high-level appeals court is an independent tribunal with worldwide jurisdiction over active-duty members of the U.S. armed forces and others subject to the Uniform Code of Military Justice.
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