A self-confessed sadomasochist – who showed a judge and jury how he was strapped to a ‘torture board’ – has been cleared of strapping a woman to the board and sending 240 volts through her genitals.

Road worker Keiren Batten, from Hitchin, claimed he was ‘branded’ and left scarred when his genitals were blowtorched by the woman against his wishes as he was strapped to it and that she carved her name into his thigh with a Stanley knife.

The jury at Cambridge Crown Court took more than eight hours to decide Batten, of Radcliffe Road, was not guilty of sexually assaulting the 27-year-old woman – who cannot be identified for legal reasons.

Jurors also acquitted the 43-year-old of one offence of common assault involving a push during an argument, but they failed to reach a verdict on a second assault relating to a head butt. The jury were discharged.

Judge David Farrell QC gave the Crown Prosecution Service a week to decide if it wanted to re-try Batten on that matter.

Defence barrister Neil Fitzgibbon had previously asked Batten to lie down on the board in court and strap himself to it using the head, body, arm and leg collars, belts and chain.

Judge Farrell came down from his bench to stand with barristers and jurors to examine Batten’s demonstration on the floor of the court.

Jurors were also shown explicit photographs of Batten’s genitals bearing the branding and burn marks.

Prosecutor Simon Wilshire had alleged that Batten ‘tortured’ the woman with his home-made electric shocker by attaching crocodile clips to her genitals while she was strapped to the restraint board he had made from plywood and pet collars and belts.

He said Batten was ‘obsessed with sadomasochistic sexual practices’, saying: “He used her to satisfy his physical, dangerous sexual desires re bondage, sadism and restraint.”

The complainant told the court she went along with some of the kinky sex – which was said to be more extreme than in the notorious book and film Fifty Shades of Grey – because he said she was boring in bed. She said she was twice electrocuted through her nipples.

But she claimed Batten on another occasion connected the lead to her genitals – although she had said he must not.

“He put the crocodile clips inside, attached to my labia, and shocked me,” she said.

“He turned it on and I just caught my breath because you think you are going to die. I have never experienced anything so hideous in my life.

“I never went on the board again. After that ‘I was rubbish in bed’ and ‘everybody else was better’, ‘I was just a prude’.”

“He calls it a torture and it is torture really. As I got a bit braver I said ‘no’ and that’s when he got bored and went elsewhere.”

In his defence, Batten said he enjoyed playing the submissive role and became sexually aroused by bondage and pain.

He said the woman had tied him naked to the board, whipped, spanked and electrocuted his nipples and testicles. He said she had also blowtorched his genitals, groin and leg, and written her name with a Stanley knife, all during the same sex session.

Batten told the court he had not consented to that, adding: “It was going too far.”

He claimed he made the board to his measurements and the woman had never gone on the board or been electrocuted.

In cross-examination, the woman accepted she carved her name with a Stanley knife into his inner thigh, but denied she used a blowtorch or the shocker on him.

Batten had earlier pleaded guilty to criminally damaging a mobile phone and taking a hammer to a wall at the complainant’s home and has been remanded in custody to be sentenced for those offences on May 2.