A military judge has ruled that army psychiatrist Nidal Hasan must be clean-shaven before his murder trial.

Hasan is charged in the 2009 Fort Hood shooting rampage. Thirteen people were killed, including Specialist Fred Greene from Johnson County, Tennessee. Thirty-two others were injured.

Hasan told the judge last week that he grew a beard because the Muslim faith requires it. Beards are a violation of Army regulation and soldiers who disobey those orders can be shaved against their will.

Hasan's attorneys plan to appeal, delaying the trial further.