It was his only relief. 

A whizzing Minnesota college professor allegedly spilled his own urine on a student’s backpack in what authorities believe to be the latest in a disturbing series of the educator’s pee-soaked incidents, according to new court docs.

The alleged piss plot was uncovered after a Macalester College student said biology professor Paul Fischer, 55, had heeded nature’s call on Dec. 5, 2025, after she briefly stepped away while working at the school’s science center – only to return to find her backpack moist with a pungent yellow liquid, CBS Minnesota reported. 

The unidentified student reported the incident and told authorities that she believed Fischer, who had been teaching at the Saint Paul university for more than 25 years, was responsible for the urination since he was the only person nearby at the time, records show.

The pissed-off pupil provided receipts estimating $2,000 in damages from Fischer’s misplaced bathroom break, according to documents.

When local cops in Saint Paul investigated the tinkling, they found that Macalester Public Safety had received six prior reports complaining about urine found in places other than the restroom at the school’s Olin-Rice Science Center, records show.

Odd places where pee was discovered included trash cans, water bottles and even inside other professors’ decorations, according to documents.

When questioned by authorities, Fischer told police he developed a strange habit over the past two years of peeing in a cup and dumping it in campus trash cans or science lab sinks, records show. 

The toilet-challenged educator told cops he may have accidentally soiled the student’s backpack while trying to dispose of a cup full of his wee into a trash can near his office, the document states.

Macalester College told CBS Minnesota that Fischer’s employment at the school ended during the 2025-2026 academic year. A criminal complaint noted he resigned as the college investigated the rash of urination incidents. 

The serial sprinkler was charged with first-degree property damage and faces five years in prison and a maximum fine of $10,000. He is expected in court in early November.

Attorney information for Fischer wasn’t readily available, and he could not be reached for comment.