In a landmark judgement with far-reaching social implications, Italy's highest appeals court has ruled it is a criminal offence for Italian men to touch their genitals in public.

The judges of the court of cassation stressed that the ban did not just apply to brazen crotch-scratching, but also to what might be termed superstitious pre-emption. Anyone who has seen a hearse go past in Italy, or been part of a discussion in which some terrible illness or disaster is mentioned, will know it is traditional for men to ward off bad luck with a quick grab at what are delicately called their "attributi".

The practice has become increasingly frowned on, but "io mi tocco i … ", which translates as "I touch my … " is still a common phrase, roughly equivalent to "fingers crossed". The judges helpfully suggested that those seeking reassurance should wait till they had returned to the privacy of their own homes before letting their hands stray trouser-wards.

The court was ruling on the appeal of an unnamed 42-year-old workman from Como near Milan. In May 2006, he was convicted of indecent behaviour for "ostentatiously touching his genitals through his clothing". His lawyer said it was merely a "compulsive, involuntarily movement, probably to adjust his overalls".

The third penal division of the Rome court was having none of it. It said that public genital-patting "has to be regarded as an act contrary to public decency, a concept including that nexus of socio-ethical behavioural rules requiring everyone to abstain from conduct potentially offensive to collectively-held feelings of decorum".

The judges said such actions risked generating "awkwardness, disgust and disapproval in the average man", unexpectedly perhaps failing to mention the average woman.

The workman was ordered to pay a €200 fine and €1000 costs.