A scaffolder who took a knuckle-duster to an anti-immigration protest after going for dinner and drinks with his teenage sons has been jailed.

Lee James, 42, of Southampton, had admitted possessing the weapon when he attended the demonstration in the Hampshire city on August 7.

Southampton Crown Court heard on Monday that James, wearing a maroon top and shorts, was spotted by a police officer in a large group of people protesting against immigration and asylum, with what looked like a knuckle-duster.

An officer approached him as he had his right hand in the pocket of his shorts, and told James if he had something in it to keep it in his pocket and leave the area.

Prosecutor Richard Onslow said James had taken the knuckle-duster out of his van to the protest “on a whim” and told police it was for his protection.

Mr Onslow said: “He had been having dinner and drinks with his two teenage sons, he had a few drinks with his meal.

“He had recently helped out a homeless man in Burger King and was upset about people like that not being helped more.”

He said he decided to go to the protest to “see what it was like” as he had not experienced anything like that before, adding: “He was scared it could be violent, he only went out of curiosity.”

The court heard he had read online about “gangs and violence” at protests and had visions of people with machetes and zombie knives at the demonstration.

Mr Onslow added that the police officer took the decision not to arrest him at the protest because the situation “would have descended into disorder”.

Later James was recorded in a video interview in the protest where he could be seen being “very blase about waving it around his hands as he spoke”.

Sentencing James, Judge Christopher Parker KC said: “Southampton is a city that lives harmoniously and you put that at grave risk.

“You chose to go along to take part in the protest, but you also chose to take with you a knuckle-duster whose only purpose can be to cause injury to other human beings.

“It would have taken very little to start a large-scale public disorder incident.”

He added: “You said you wore it to protect yourself but you wore it openly, you were not under any threat.”

In court, James nodded as his defence barrister, Lucie Taylor, said he would be the “first to admit he made a stupid decision and probably the worst decision he has ever made”.

Ms Taylor said the consequences of a custodial sentence would be wide-reaching on his children, who he financially supports, but also his business and employees, who rely on him for their work.

James was given a 12-month prison sentence, to serve half of the period before being released on licence, and a further 12 months post-sentence supervision.

He gave a thumbs up to his supporters in court as he left the dock.