Breaking News: He rubbed lemon juice on his face. Robbed two banks. Smiled at the cameras. Got caught in an hour. And changed psychology forever….see more

In 1995, McArthur Wheeler walked into two banks in Pittsburgh and robbed them with no mask, no disguise, and lemon juice on his face.

He believed that because lemon juice works as invisible ink on paper, it would make his face invisible to cameras. He smiled directly into the security cameras. Police aired the footage on the evening news and arrested him within an hour.

When shown the tape, Wheeler stared at the screen and said, “But I wore the juice.” He had tested the theory with a Polaroid selfie and didn’t appear in the photo — because lemon juice got in his eyes and he aimed the camera at the ceiling.

His case inspired Cornell psychologists David Dunning and Justin Kruger to publish their 1999 paper defining the Dunning-Kruger Effect — the cognitive bias where people with low ability drastically overestimate their own competence.