( CNN ) -- The judge in the court-martial of an Army psychiatrist charged in a deadly shooting spree on a Texas military base rejected options presented by his lawyers under which he would plead guilty and ordered the trial to begin in May . Maj. Nidal Hasan is charged with killing 13 people at Fort Hood in November 2009 , called the worst incident of its kind on a military base . Col. Tara Osborn on Wednesday ruled that pre-trial publicity around the case would not unfairly prejudice a jury and set the start of jury selection for May 29 . Testimony is scheduled to begin July 1 . Hasan 's lawyers filed motions indicating that he was willing to plead guilty under three potential scenarios . Details of the proposals , including the counts involved , were not immediately clear . But Osborn turned them down , saying it would be tantamount to admitting guilt to a capital offense , which is not permitted under military law . Hasan , who was paralyzed from the waist down in an exchange of gunfire with police , appeared bearded and thinner when he arrived for the pretrial hearing in a wheelchair . The attack that resulted in murder and attempted murder charges against him occurred at the post 's processing center , where soldiers were preparing to deploy to Afghanistan and Iraq . 2012 : U.S. asks court to deny Fort Hood shooter 's appeal . Prosecutors aim to show that Hasan was a radical Islamist . Investigations have found that he had been communicating via e-mail with Anwar al-Awlaki , a prominent radical Yemeni-American cleric killed by a U.S. drone attack in 2011 . And much of Wednesday 's hearing was devoted to questioning a potential expert witness for the prosecution , Evan Kohlmann , an international terrorism expert who apparently examined the contents of a laptop belonging to Hasan . Kohlmann said he found examples of websites and YouTube videos that could indicate someone trying to learn more about radical Islam . He said there was `` no indication that anyone other than Hasan used the laptop . '' One item on the laptop that was cited by Kohlmann linked to a YouTube video of a 2009 CNN report featuring the network 's national security analyst , Peter Bergen , talking about a newly released audio tape from Osama bin Laden . Defense lawyers , who want to keep Kohlmann off the stand at trial and sought to undercut his methodology and conclusions , introduced their own expert witness who said that only a portion of the CNN report had been viewed . The start of Hasan 's court-martial has been repeatedly delayed since it was initially set to begin in March 2012 , most notably after an appeals court delayed the case over the question of whether the Army major 's beard could be forcibly shaved . Army regulations prevent soldiers from wearing facial hair while in uniform . Hasan , who is still considered a soldier , is a practicing Muslim and maintains he has the right to wear the beard under U.S. laws protecting religious freedoms . 2012 : Fort Hood suspect 's beard focus of another hearing . The case resumed after a higher court dismissed the order that Hasan be shaved and replaced the judge in the case . If convicted , Hasan faces a possible death penalty . A U.S.-born citizen of Palestinian descent , he was a licensed psychiatrist who joined the Army in 1997 . He had been scheduled to deploy to Afghanistan before the killings , but had been telling his family since 2001 that he wanted to get out of the military . Hasan had told his family he had been taunted after the terrorist attacks of September 11 , 2001 . Investigations tied to the Fort Hood shootings found he had been communicating via e-mail with Anwar al-Awlaki , a prominent radical Yemeni-American cleric killed by a U.S. drone attack in 2011 . 2012 : Fort Hood shooting victims want rampage labeled as terrorism . 2012 : Military judge removed from Fort Hood shooter case . 2012 : U.S. asks court to deny Fort Hood shooter 's appeal .
NEW : Judge rejects requests for settlement settlements from Hasan 's lawyers . The 2009 shooting that killed 13 soldiers occurred at the post 's processing center . NEW : Prosecution expert witness discusses evidence apparently found on Hasan 's body . Hasan appears in military court thinner , bearded , in wheelchair .