A senior police officer accused of setting fire to his own car and letting his lover's husband face arrest over it today denied the arson attack.

At Swindon Crown Court, Chief Supt Jim Trotman, 45, rejected the prosecution claim he had doused his Citroen Picasso in petrol and set light to it near the home of his married lover, Karin Gray.

Trotman, who works for Thames Valley Police, denies charges of arson, attempting to pervert the course of justice and two counts of fraud by false representation.

Trotman told jurors: "I did not set fire to my car and I find it incredible that people think I have.

"By the fact I am standing here in the dock means I have questions to answer as it was my car and it was my petrol can.

"I am a very angry man. It has had a huge impact upon my life."

His car was burnt out after he left it close to his Mrs Gray's home in Bedwells Heath, Boars Hill, near Oxford, on the night of October 20, 2009.

In a statement given to police later that night, Trotman said he had parked away from Mrs Gray's home and then taken the five-minute walk through woodland to her house, arriving shortly before 10pm.

He said he left her house at 11.30pm and walked back to his car where he discovered it burnt out and the police and fire brigade at the scene.

However, in court today Trotman accepted that mobile phone records have him arriving at Boars Hill later and place him in the vicinity when the car was set alight shortly before 10.30pm.

Jurors have already been told that Trotman, a father-of-two, had on the afternoon of the arson attack shown a senior police colleague several emails purporting to show that Mrs Gray's husband knew of the affair and had hired a private investigator.

Trotman, who was separated from his wife Charlotte, had not corrected the impression that solicitor Ian Gray had set fire to his car after discovering the 20-month affair.

Mr Gray, who works for top London law firm Eversheds, was arrested on October 21 on suspicion of conspiracy to commit arson. He was later fully exonerated.

One email, dated October 19 from sender 'iangray666', said: "The Wood House remains out of bounds for you Mr Trotman. Please confine your contact with Karin to the leisure centre. Your co-operation is appreciated."

Recalling the conversation with Detective Superintendent Ashley Smith, Trotman told jurors: "Did he take me seriously? That's a good question.

I was surprised by the sterile nature of the advice to stay away (from Mrs Gray's house).

"I think he took me seriously at the time.

"I listened to the advice, weighed it up and decided not to. I did not ignore it; I decided not to follow it.

"Karin Gray was in a considerable state of distress that night. Those emails had been going on for about a week.

"It appears that somebody knew her husband was going away that night and knew that her husband had been to see a divorce lawyer in Nottingham on two previous occasions."

Under cross-examination by prosecutor Fiona Elder, Trotman accepted he thought Mr Gray could have been behind the threatening emails, although he said that he never thought Mr Gray had sent the emails himself but could have arranged for someone else to send them

"I did not say I was very suspicious (of Mr Gray). I certainly believed he could have been behind them," Trotman told the court.

After the arson, Elephant Insurance paid out GBP14,820 and The Warranty Group - with whom Trotman had a policy insuring against the loss of the value of the car - paid GBP4,880.

He used the insurance money to buy an Audi A4 convertible, the court heard.

Trotman joined Thames Valley Police in 1992 having served in the Royal Marines, where he saw active service in Northern Ireland and Iraq.

At the time of his arrest he was head of the force's strategic development department and was the former police commander for Oxford.

Trotman, of West Quay, Abingdon, Oxfordshire, denies arson, attempting to pervert the course of justice and two counts of fraud by false representation.

Judge Douglas Field adjourned the trial until tomorrow.