Dr David Jenkins is furious after a Criminal Records Bureau blunder erroneously stated he had a conviction for possession of cannabis.
He is now being forced to have a fingerprint test to prove his innocence.
The certificate sent to Dr Jenkins, a GP in Carmarthenshire, was littered with errors, including a wrong date of birth, a missing middle initial and the conviction for cannabis possession in Loughborough in 1976.
Dr Jenkins said: 'I keep telling them they must have sent the wrong certificate but they say I have to dispute the offence. It's crazy.'
A CRB spokeswoman said it had to err on the side of caution.