Sajid Hussain Raza, 43, Shabana Hussain, 40, and Daud Khan, 44, were convicted by a jury at Leeds Crown Court of making payments into their own bank accounts from Department for Education grants given to help set up the Kings Science Academy in Bradford in 2011.
The defendants showed no emotion as they stood in the dock and listened as the jury foreman returned unanimous guilty verdicts on all charges.
The jury of five men and seven women had been deliberating for just over one day after hearing evidence in the six-week trial.
Judge Christopher Batty told the defendants: “You have been convicted of serious offences and I am very much considering custody in each of your cases.”
The academy was praised by then prime minister David Cameron during a high-profile visit in March 2012. It has since become part of the Dixons Academies Trust and is now called Dixons Kings Academy.
The trial heard that Raza, the founder and principal of the school, used some of the money to make mortgage repayments on rental properties he owned to alleviate his own financial problems.
But he told the jury the suggestion he used public money to cover his debts was “unbelievable’’.
The fraudulent activity continued for three years, between November 2010 and December 2013, despite senior civil servants expressing concern about his leadership and financial management.
Raza was found guilty of four counts of fraud, three counts of false accounting and two counts of obtaining money by deception.
Hussain, a teacher at the school and Raza’s sister, was convicted of one count of fraud and one count of obtaining property by deception.
Khan, the financial director at the school, was found guilty of two counts of fraud and three counts of false accounting.
The jury heard that a number of meetings took place between Raza and the Department of Education, at which he was said to be “incredibly rude and dismissive”, appeared to “pluck financial figures out of the air” and threatened to call the then education secretary Michael Gove when challenged.
Kings Science Academy was among the first wave of free schools set up as part of a flagship education policy introduced by the government following the 2010 general election.
The court heard that Raza made an application for a 500-place secondary school to open in September 2011.
The proposal was approved and grants were given by the Department of Education to cover the costs incurred during the setting up of the school.
But Raza and Hussain, both from Bradford, made a series of payments into their own personal bank accounts from these grants.
Khan, from Thornbury, Bradford, did not receive any payments but helped Raza by submitting inflated or fabricated invoices for rent, fees for heads of department and recruitment services.
Raza also made false claims about his income and job on mortgage application forms in 2004 and 2008, when he began having financial problems.
Rental properties owned by Raza were making a loss and he began missing direct debit and mortgage payments due to having insufficient funds in his bank accounts.
A number of county court judgments were entered against him, which he did not disclose to the Department of Education, and he was unable to become a signatory to the school’s bank account.
Raza opened a bank account in 2010, which had a balance of £28,000 in July 2011 after it was used to receive three large credits from the Kings Science Academy.
Almost half of that balance was used, in the same month, to make large mortgage repayments.
All three defendants denied any fraudulent activity.
The trio were granted bail until a sentencing date in September.
The Crown Prosecution Service said Raza, who was photographed alongside Mr Cameron during the former prime minister’s visit to the school in 2012, was motivated by his financial difficulties.
Peter Mann, head of the complex casework unit, said: “Far from being a model school, Raza treated the academy like a family business, employing his relatives there and, for at least the first 12 months, operating with no proper governance.
“His co-defendants were also drawn into this criminality. Hussain, Raza’s sister, received unlawful payments, and Khan helped to falsify documentation.
“The defendants treated public money as their own and, when challenged, fabricated documents to cover their tracks.”
Detective Superintendent Jon Morgan, of West Yorkshire Police, added: “Raza, Hussain and Khan were in positions of trust, stealing thousands of pounds of public money which was intended for the development of a newly formed academy.
“They acted selfishly and dishonestly in obtaining these funds and I would like to thank everyone who has helped uncover their unscrupulous activities and brought them to justice.”