A RETIRED detective was yesterday accused of subterfuge in his investigation of a senior policeman accused of torching his own car to implicate a love rival.

Chief Superintendent Jim Trotman, 45, is accused of setting his Citroen C4 Picasso on fire to implicate Ian Gray, the husband of Karin Gray, a woman he was having an affair with.

Jurors at Swindon Crown Court heard father-of-two Trotman, who was separated from his wife, told Det Supt Ashley Smith of the affair hours before the fire on October 20, 2009 in Jarn Way, Boars Hill, Oxford.

Mr Smith then went on to become the officer investigating the case and yesterday the jury heard John Beggs, defending, question his investigation.

Mr Beggs said: “If you suspect someone of a crime you are under a duty to caution them. “You interview this guy repeatedly without him knowing you were making notes.”

Mr Smith said he had thought Trotman was a “genuine victim” and had decided to tap the father-of-two’s phone from October 26 to work out if he was involved or not.

Mr Smith, who retired in June, said: “I did not want to put in the minds of senior officers that there was something dodgy about him. I thought that was a good way to do it.”

Mr Beggs also questioned why it took 12 days before a large petrol can was found 60 feet from the car. Trotman told police on October 26 about a can being in the car and Mr Smith said a search was not carried out for anything like it beforehand as he felt there was no need.

He said Trotman, from Abingdon, told him on the day of the fire of the affair and emails purportedly from a Kevin O’Hara and then the email address Iangray666@hotmail.com.

he latter claimed to have got Trotman’s details from the Boar’s Hill Swingers Association and alleged Trotman had got Mrs Gray pregnant.

They threatened to inform Mr Gray, jurors heard, and told him to stay away from the Grays’ home in Boars Hill.

They were found to be from Kai Reeves, but he was eliminated from the investigation.

Mr Beggs said: “You eliminated him from in late April, several weeks after you had already charged Mr Trotman. You were going through the motions.

“He was a person you wanted to swat out of the way because you had a more likely candidate for the fire.”

Mr Beggs said: “You’d got your man and you were feeling great because you could go out and retire thinking ‘I have got the scalp of a senior officer’.”

Mr Smith denied that was true. Trotman, who is still with Mrs Gray, denies arson, perverting the course of justice and two counts of fraudulently claiming insurance. The trial continues.