An employee of Haliburton, Choon Ping Lee, had charges filed against him after a first class passenger found a hidden camera in the lavatory.

A woman flying in first class on the flight went to use the bathroom and “noticed an item with a blue blinking light” that was “located near the cabinet and wall area close to a door hinge,” according to the criminal complaint.

The owner of the camera wasn’t visible on any of the footage recovered from the recording device but there were a few clues that led authorities in the right direction.

According to the complaint, security viewed footage on the camera and saw the man who installed it on the plane was wearing a watch on his left wrist and small bracelet on his right, as well as a blue short-sleeve shirt and blue jeans. They could not, however, see the man’s face.

The left wrist and small bracelet ended up being the key evidence in the case. Reviewing security footage led authorities to Choon and they were able to piece together previous itineraries that were also included on the camera.

Lee is facing up to one year of prison for his despicable acts.