Misconduct hearings - most of which collapsed - against teachers accused in the so-called "Trojan Horse" inquiry cost £884,055, the BBC can reveal. The case to ban from education the ex-chair of governors for three Birmingham schools that were investigated, Tahir Alam, also cost £387,444 in legal fees.
Witness statements from a prior inquiry had been "deliberately withheld" before the hearings were dropped in May 2017. The government said it made "no apology for working to protect young people".
The BBC has fought a Freedom of Information battle since April 2017 to reveal the costs, which succeeded when the independent data watchdog The Information Commissioner's Office ordered the Department for Education (DfE) to release the information after backing the corporation's public interest arguments.
The only teacher who was sanctioned - out of 14 against whom the DfE pursued hearings - was the former acting head teacher of Oldknow Academy in Small Heath, Jahangir Akbar.
Banned governor Mr Alam said the cases were a "total waste of public money" that achieved little. Several schools in Birmingham were investigated amid claims of a Muslim hardliners' plot to control them, known as the Trojan Horse affair, which began in 2014.
The teachers' hearings stemmed from that investigation but were dropped when the professional conduct panel of the National College for Teaching and Leadership (NCTL) found its own organisation withheld 25 statements that had been used in an an earlier inquiry led by former counter-terror boss Peter Clarke.
The DfE said it was "looking carefully" at the handling of the cases, which were "led by an external law firm". The teachers were not permitted to work while the hearings, which began in 2015, were ongoing. Lawyers for two of the accused teachers, Monzoor Hussain and Lindsey Clark, had issued separate statements when the hearings were dropped saying both parties were relieved.
The inquiry has "caused long-term damage" and "divided communities" in Birmingham, according to the co-author of a play about it, Helen Monks. The alleged plot caused such outrage because the accusation centred on the claim children were being fed a one-sided education and view of the world.
Ironically the hearings collapsed when the NCTL - which has since been replaced by the Teaching Regulation Agency - found it had not presented the whole picture of the accusations to the lawyers who were trying to defend the accused teachers' reputations and careers.
Mr Alam said he was depicted as an "anti-state enemy" during the affair and questioned what the inquiry achieved. He said GCSE marks at the schools where he was chair of governors had declined since the affair.
