Michael Ruse, 21, believed the two week trial had gone well and decided to share the news online before the jury was due to go out.

Ruse, who had denied beating up a friend's dad, wrote a status update shortly before the jury was due to go out, saying: "Another week at court!"

When asked by a friend about the case he said: "Yeah I think I get away with it tbh (to be honest) x," adding it was "looking good."

The exchange was printed out and delivered anonymously to the court, where it was handed to the prosecution.

Confronted by the new evidence Ruse, who used the name Michael Miles online, had little choice but to change his plea to guilty to assault causing actual bodily harm.

Ruse, who has previous convictions for assault and criminal damage, then went back on the social networking site to describe the judge as "stuck up" hours before his sentencing.

Judge Ian Pearson said Ruse's stupidity was no excuse.

He said: "You pleaded guilty part way through the trial only really because you were stupid enough to put on Facebook what amounted to a full confession.

"Your stupidity really is not much mitigation."

Ruse, of Leigh Park, near Portsmouth, Hants, was given a 46 week prison sentence, suspended for two years, and put on a six month curfew from 7pm to 7am.

Russell Pyne, defending, said his client had planned to move away from Leigh Park and change his ways.

He said: "He needs help with regards to thinking skills."

During the trial, Portsmouth Crown Court heard Ruse's friend, Terry Reeve, 20, had thrown a brick at his own dad's car earlier in the day in March last year.

Ruse and Reeve then armed themselves with a baseball bat and a baton and attacked the 45-year-old lorry driver in the street in Leigh Park.

Reeve's father was left with a cut to his head and bruises all over his body.

Reeve, of Leigh Park, was found guilty of the assault and of criminal damage after the trial. He was jailed for a year and 55 days.

Michael Williams, defending Reeve, said he had not had a happy childhood.

He said: "The reason that he perhaps thinks with his fists first comes from his father."

After the hearing, Ruse went back on Facebook to say: "Boom! Im (sic) coming home best start sorting myself out. Tag for 6 months...and got to stay out of trouble for 2 years."

He was also fined £250 in court costs.