What is Egypt's ousted President Morsi being tried for?

Another former president of Egypt is going on trial. Mohammed Morsi, the Islamist leader who became the country's first freely elected president only to be ousted by the military after a year in office, faces charges he incited his followers to kill protesters.

The trial is a new landmark in Egypt's 2 ½ years of turmoil since autocrat Hosni Mubarak was toppled. Morsi's supporters have been protesting since he was removed on July 3. Hundreds have been killed in clashes, and authorities have arrested more than 2,000 members from his Muslim Brotherhood. Officials, the media and a broad swath of the public contend the Brotherhood have proven themselves a threat to the country, while the group says the military is crushing democracy.

Here is a look at the case against Morsi and 14 Brotherhood members on trial with him — and the politics around the case.

Q: What are the charges based on?

A: The charges are rooted in violence that erupted during one of the first major protests against Morsi during his year in office. On Dec. 4, some 100,000 people protested outside the presidential palace against Morsi's decree granting himself sweeping immunity from judicial oversight. The decree allowed his Islamist allies to push a disputed draft of the constitution toward adoption without court challenge.

The protesters demanded he call off a referendum on the draft scheduled days later. Some scuffled with police outside the palace gates. Morsi left the palace from a backdoor, and his convoy was heckled. He later said one of his drivers was injured. A few thousand protesters set up a camp outside the palace while the Muslim Brotherhood called for a "general mobilization" of members.

The next day, Islamists attacked the camp, tearing up tents and beating protesters. Videos at the time showed them marching in military-style lines and chanting, "God is great" and "Morsi's men are everywhere."

More anti-Morsi protesters streamed to the scene, and street battles lasted into the early hours of the next day, each side throwing stones and firebombs.

Amid the melee, Brotherhood members abducted protesters and held them in a makeshift room at the palace gates, beating them to confess they were paid thugs, according to later statements by those who were held. The next day, they handed the detainees to the police. A prosecutor later freed them, saying there was no evidence against them but that his Morsi-appointed boss had pressured him to implicate them.

At least 10 people were killed in the battle. One was a journalist who wrote articles critical of Morsi. The Brotherhood claimed all the dead were its members, but the families later said the group pressured them to say their slain relatives belonged to the Brotherhood.

A: Isn't this just a political show trial?

Q: That's complicated. Human rights lawyers say on the face of it, this is possibly the strongest case against Morsi. Laywers tried to raise a case against Morsi over the Dec. 5 violence soon after it happened, giving some credibility to arguments it is not purely based on post-coup vengeance. (Under the Morsi-appointed chief prosecutor and justice minister at the time, the attempt went nowhere.)

However, this trial comes as part of the wide crackdown against the Muslim Brotherhood aimed at crushing it as a political force as the new military-backed government moves ahead with its own transition plan.

The Brotherhood says the charges are baseless and the planned trial a sham, aimed at giving legal cover to the coup.

There are concerns over how fair the trial will be. Morsi has been held in secret military detention undergoing questioning since his ouster, virtually incommunicado except for two calls with his family and visits by the EU foreign policy chief and an African Union delegation. He has not spoken to his legal team, which says it hasn't been given documentation on the prosecution's case.

Another issue reflecting the politics: Trials are selective. No one is prosecuting the military or police over deaths of protesters. Human rights lawyers say officials in office are almost never held to account.

Q: What is the evidence against Morsi?

A: The prosecution's case has not been made public. Morsi at the time accused the protesters of starting the violence.

In parts of the investigation leaked to the Egyptian press, the head of the police force at the time said he refused to use force to break up the unarmed protesters outside the palace, so Morsi called out his supporters to do so. According to the press reports, the head of the Republican Guards — which protect the palace — said Morsi gave him a one-hour ultimatum to forcefully break up the sit-in. The Guards chief said he asked for more time to disperse it peacefully, and one of Morsi's aides told him "our men" will take care of it.

At the height of the fighting, leading Brotherhood member Essam el-Erian went on the group's TV station and called for Morsi supporters to go to the scene "in the tens of thousands to besiege those thugs because now is the moment to arrest them." El-Erian is now a co-defendant in Morsi's trial, though he is currently on the run and in hiding, so would be tried in absentia unless caught.

At the time, the organized nature of the attack on the camp fueled accusations by opponents that the Brotherhood runs "militias" to crack down on opponents, a claim the group denies.

Q: Any other trials coming up?

A: The Brotherhood's top leader, Mohammed Badie, and several other members are already on trial on incitement charges over a separate incident of violence. Prosecutors are preparing cases against some 2,000 Brotherhood members currently in prison, including on allegations of including inciting violence in clashes outside the Brotherhood headquarters in Cairo and holding and torturing policemen during a pro-Morsi sit-in.

Morsi could also face more trials. He is being investigated on charges of insulting judges when, during a presidential speech, he accused specific judges of helping rig elections under Mubarak. Another case concerns allegations he colluded with Hamas to carry out attacks on prisons that broke free Morsi and other Brotherhood leaders during the 2011 anti-Mubarak uprising.

Q: Speaking of Mubarak, he's still on trial?

A: Yes. In June 2012, he was convicted and sentenced to life in prison for failing to stop the killings of the around 900 protesters who died in 2011 uprising But an appeals court overturned the conviction, saying the prosecution failed to provide concrete evidence. Mubarak's retrial began last spring.