The fourth session of Hosni Mubarak's trial in Cairo today took place behind closed doors, but that hasn't prevented reports of the tumultuous proceedings from surfacing. The session got off to a rocky start as soon as the former Egyptian president, who is charged with corruption and complicity in the killing of protesters, arrived at the courtroom on a stretcher. Arguments between pro- and anti-Mubarak lawyers delayed the proceedings and later forced the judge to call two recesses. The former head of Egypt's bar association and some of the lawyers representing victims' families withdrew from the hearings because of the "chaotic" conditions inside the courtroom, according to Al Jazeera

The trial is facing another obstacle beyond bad blood: bad witnesses. The judge ordered the arrest of a key prosecution witness today on charges of perjury after suspicions surfaced about the testimony of four previous witnesses, in what the AP is calling a "deep embarrassment to the prosecution." On Wednesday, Captain Mohammed Abdel-Hakim denied he had any knowledge that police were armed or given orders to shoot protesters, after previously telling prosecutors that he had been ordered to fire on demonstrators and had distributed bullets to his soldiers. Some lawyers for families of slain protesters have accused senior Egyptian officials and Mubarak supporters of leaning on the witnesses to change their stories in favor of the defense, and have demanded a change of judge and new witnesses in light of the contradictory testimony.

Then there's the matter of the Kuwaiti lawyers who are helping defend Mubarak. The volunteer lawyers say they've come to the former Egyptian leader's aid because Mubarak supported a U.S.-led coalition to remove Iraqi forces from Kuwait in 1991. But, as Al Jazeera points out, the "request has piqued many Egyptians, who see the trial of their former president for 30 years as an internal matter."

Still, for all the tumult, today's session didn't spark the kind of violent clashes outside the courtroom between protesters and police that took place during the trial's third session on Monday, and produced images like the one below. And Wednesday's court appearance also generated what appears to be good news for victims' families: Field Marshal Mohammed Tantawi, Mubarak's former defense minister and current military ruler, will soon testify along with Omar Suleiman, Mubarak's vice president and intelligence chief, about Mubarak's role in putting down the Egyptian uprising.