A motorist refused to carry out a breath test for police because he believed he would pick up a disease from a breathalyzer.
Krzysztof Nowak gave the reason for the refusal when he admitted failing to provide breath specimens when he appeared in court on Thursday.
Nowak, 24, was banned from driving for a year and fined £600 when he admitted failing to provide breath samples on January 15 this year at Perth Police station.
Solicitor Cheryl Clark, defending, said: "When he was given the device by the officer he was frightened of contracting something from the device by breathing into it and touching it. There is no medical reason for not giving a sample other than his aversion to doing so, so he accepts he did fail to provide a sample when asked to do so by the officer.
"I know from my discussions with him that he is a man who does become nervous and is quite easily upset. By his nature, that is what he is like. That may go some way to explaining his reaction when he was called over by the police."
Nowak, of Strathmore Avenue, Coupar Angus, was pulled over by police on the A923 Muirhead to Blairgowrie road after witnesses reported seeing him weaving around the road and overtaking at speed on blind bends.
The Polish national was initially charged with driving dangerously and at excessive speed while bending down to search the footwell of his Audi for a dropped cigarette lighter.
However, the Crown accepted a not guilty plea to that charge and he admitted a second charge of failing to provide breath samples at the police station.
Fiscal depute Rebecca Kynaston told Perth Sheriff Court: "The accused's driving caused some concern. He was followed by a police sergeant in a marked vehicle.
"Two further officers attended in their vehicle and he was stopped due to the manner of his driving. He was required to provide a breath specimen and warned of the consequences of his failure to comply.
"At this time the accused became incoherent and held his head in his hands and started to cry. He attempted several times to provide a specimen of breath. However, each time he appeared to purposely block the tube, preventing a sample being given.
"He was arrested for failing and taken to police HQ in Perth. He then refused to provide a specimen or comply with the procedure."
Ms Clark told the court that Nowak had been out with friends during the evening and was driving them home as a favour, but denied that he had been drunk.