A search of his vehicle discovered hundred of business cards for "McGregor Enterprise", boasting the "Best drops in Surrey", the Irish Post reported.
After the 34-year-old was arrested, they searched his home and found a sizable amount of boric acid — commonly used by dealers to cut drugs — as well as a large meat cleaver near his bed.
A subsequent search of his phone turned up more text message evidence linking him to drug dealing activity.
He was sentenced to three years in prison by Guildford Crown Court earlier this month, after pleading guilty to possession with intent to supply class A drugs, driving while disqualified, and driving without insurance.
The real McGregor of course has had a number of brushes with the law, but has yet to do any jail time.
In 2018 he was sentenced to five days of community service and ordered to atttend anger management classes after throwing a metal dolly through the window of a bus carrying rival Khabib Nurmagomedov in New York.
A year later he escaped with just a €1,000 fine in his native Ireland for punching an elderly man in a pub — although he also paid the victim a settlement of an undisclosed (though likely much larger) sum.
That same year he was accused of strong-armed robbery and misdemeanor criminal mischief, after he allegedly smashed a fan's phone; the victim later dropped the charges (but that too came with a civil lawsuit settlement.)
Just this month charges relating to an "attempted sexual assault and sexual exhibition" in Corsica were also dropped for lack of evidence.