Anse Ghesquiere told Reuters that in "another unfortunate coincidence" her client works at a brewery, but three doctors who independently examined him confirmed he suffered from ABS.
Belgian media said that in the verdict, the judge emphasized that the defendant, who was not named in line with local judicial custom, did not experience symptoms of intoxication.
The Bruges police court, which acquitted the man, did not immediately reply to an email from Reuters.
Lisa Florin, clinical biologist with Belgian hospital AZ Sint-Lucas, explained that people with the condition produce the same type of alcohol as the one in alcoholic drinks but that they generally feel less of its effects.
She added that people are not born with ABS but can get it when they already suffer from another intestine-related condition.