A science teacher in Sacramento, California, was cleared by school district officials last week after he was accused of forcing a 14-year-old boy to urinate into a bottle during one of his lessons.
The district concluded that the pupil at Goethe middle school had acted of his own accord, and that the teacher, Peter Stanzler, had told the boy he could go once the class had settled.
"Less than five minutes into the class period, the student urinated into a bottle and discarded it in a trash can," the district said in a statement.
"Shocked at the student's actions, the teacher told the student to dispose of the bottle in the restroom and wash his hands."
As punishment, the pupil was briefly suspended, while the district decided it was best if the teacher were moved to another school.
But this has not been the end of the icky affair.
Campaigners are demanding that Mr Stanzler be fired, suggesting that the white teacher had picked on the teenage boy because he was black.
The National Association for the Advancement of Colored People has described the incident as "a civil rights issue".