A knife fell out of a man’s trouser pocket as he was led from a pub by police.
Lewis Markham earlier had a flick knife in his hand as he talked to the manager inside The Lincolnshire Poacher, Spalding.
Prosecutor Kate Minihane told Boston Magistrates’ Court that Markham had wanted to talk to the owner but instead spoke to the female manager to “exonerate himself” over something.
“It was at that point that someone in the pub could see he was holding a knife behind his back and flicking it open.
“Somebody else saw him putting it down his trousers,” said Miss Minihane.
“Police were called. They noted he was under the influence of alcohol.”
As he was being led out, Markham reached into a pocket and a metal cylinder fell to the floor, with a five-inch blade springing open.
“This item has the potential to cause serious harm. He said he carried the knife for protection because he had been stabbed before,” said the prosecutor.
Markham pleaded guilty to having an offensive weapon in a public place.
He said in mitigation: “The only reason I was carrying that knife was that I was going to have a few pints and self-harm.”
Asked by the bench whether he was receiving mental health support, he replied: “It’s a big step for me to accept that I do need help with my mental health.”
The case was adjourned to August 9 for preparation of a pre-sentence report.
Markham, of Bowgate, Gosberton, was granted unconditional bail.