Twenty-nine former Turkish police officers went on trial in Istanbul on Tuesday for their alleged role in July's failed coup, the first trial in the metropolis as President Recep Tayyip Erdogan extends a crackdown on alleged putschists and the opposition.

Some 40,000 people suspected of playing a role in the failed coup have been arrested and tens of thousands more suspended or fired from their jobs under a state of emergency that has roiled the nation.

Amid a heavy security presence at the Silivri prison outside Istanbul, judge Fikret Demir read the indictment against the police officers accused of belonging to a terrorist organization and disobeying orders to defend Erdogan's palace in Istanbul on the night of the coup.

Twenty-one of the defendants face three life sentences if convicted, while the other eight officers face jail time of between 7.5 years and 15 years. Twenty-four of the defendants are under arrest, one on the run and the rest were released from jail on bail pending the trial.

"Everyone involved in the coup attempt must have a fair trial," Orhan Cagri Bekar, a state prosecutor, told reporters. "Those who are guilty must be sentenced to the heaviest punishment because this is a betrayal of the country."

Turkey accuses US-based cleric Fethullah Gulen and his followers of orchestrating the coup attempt, in which rogue soldiers used tanks, fighter jets and helicopters to bomb parliament and take over the streets before being defeated. Nearly 250 people were killed.

Gulen, an ally-turned-foe of Erdogan and Erdogan's ruling Justice and Development Party, denies any involvement.

Many more coup trials are expected to start next year, raising questions about the ability of an overburdened and politicized judiciary to provide fair trials as the rule of law in Turkey deteriorates. The government has so far only provided circumstantial evidence of Gulen's direct involvement and allegations of torture further cast doubt on testimonies. Pro-government media has also ramped up accusations and conspiracies about the so-called Fethullah Gulen Terrorist Organization/Parallel State Structure.

The government continues to use broad state of emergency powers to arrest suspected followers of Gulen, who authorities say over at least three decades infiltrated the military, police, judiciary, media and other institutions. In the past week, more than 1,000 people have been arrested.

Thousands of people accused of being supporters of Gulen but who had no direct involvement in the coup may be swept up in the trials. There is concern that soldiers and police may have unwittingly followed orders on the night of the coup, not knowing that they were under the command of the putschists.  

The state of emergency powers have since been used to target the opposition and media, including the pro-Kurdish party in parliament, drawing international concern over the extent of the crackdown. The crackdown comes as Erdogan seeks an expanded presidency that will remove many checks and balances on his power.

The location of the trial at Silivri reminds Turks of two other coup plot trials known as Ergenekon and Sledgehammer, designed to clip the wings of the secular military.

Erdogan and Gulenist prosecutors led the charge in those multiyear trials, in which several hundred military officers, opposition politicians, academics and journalists were convicted. At the time, critics of the trials pointed to widespread evidence fabrication and distortion.

All the suspects were released in 2014 and 2015 after Gulen and Erdogan had a falling out over a corruption scandal and the courts squashed the verdicts.

cw/sms (AFP, AP, Reuters)