The Crown Prosecution Service is not going to appeal against a judge's decision not to jail a Birmingham man who took a loaded gun into a nightclub.
Edwin Hayward, 23, was given a 200 hour community punishment order for having the converted air pistol in the Garry Owen club in Small Heath, Birmingham.
The sentence has been criticised by anti-gun campaigners but no further action is to be taken by the CPS.
A spokesman said it is not the type of case the body can appeal against.
Hayward, of Finstall Close, Nechells, was convicted of possessing a firearm in a public place at Birmingham Crown Court on Monday.
Review needed
He claimed he had found the gun in a car park and thought it was a cigarette lighter.
The police have said they are going to challenge the sentence.
Labour MP Steve McCabe, who represents Birmingham Hall Green, said the offence merited a custodial sentence and that Hayward's story had been absurd.
Mr McCabe has now called for a review of the CPS appeals system by the Home Office and Lord Chancellor's Department.
"The whole issue is to make sure that these sentences are broadly consistent and that where decisions are made that are completely out of step with what one would normally expect that can be addressed," he said.
"If the CPS are suggesting that this is a category of offence where their powers are rather limited we need to tackle that."