April Casburn's high-flying career in the police ended in disgrace last night when she was convicted of offering to leak details of the phone-hacking inquiry to the News of the World.
The Detective Chief Inspector, one of the country's few top female counter-terrorism officers, stood impassively in the dock at Southwark Crown Court as she was found guilty of misconduct in public office.
She became the first person for six years to be convicted for a crime arising out of the phone-hacking scandal.
The judge, Mr Justice Adrian Fulford, warned Casburn that she faced a jail term, raising the prospect that she will be separated from her newly adopted three-year-old child.
A brief, early-morning phone call to the News of the World on Saturday 11 September 2010 wrecked her 20 years of unblemished service in the Metropolitan Police.
Casburn, pictured, 53, from Chelmsford in Essex, spent her first seven years with the London force in child protection. By 2009, she was running the National Terrorist Financial Investigation Unit in Scotland Yard's counter-terrorism command SO15.
She had grown disillusioned with the male-dominated anti-terrorist command, where, unlike more junior male officers, she had been left without a desk. She was also struggling personally; her second marriage was crumbling. She told Southwark Crown Court that she became infuriated when she discovered in September 2010 that S015 would be carrying out Operation Varec into fresh allegations that phone hacking had been rife at the NOTW.
Five days after the inquiry was set up, at 7.51am on Saturday 11 September, she called the NOTW and spoke to newsdesk editor, Tim Wood. At 8.17am, Mr Wood sent an email to the NOTW's news editor and crime editor, saying an unnamed senior policewoman wanted to sell "inside information" on the hacking inquiry.
Mr Wood suspected the call was a sting. No story appeared and no payment was made. Scotland Yard later found the email in News International's database, and Casburn admitted that she had called the paper, but insisted she had been acting as a whistleblower to draw attention to the waste of counter-terrorism assets and had not asked for money.
But she struggled to explain why of all the media outlets in Britain, she had called the NOTW.
Casburn's lawyer asked the judge to spare the officer jail on account of her child, but he said a custodial sentence was a real possibility and adjourned sentencing until the end of this month.