I was accused of plagiarism back in college.

I was taking a programming course. Turned in an assignment... And the professor later wanted to speak to me. She accused me of plagiarism. Explained how it was OK to work with other people on an assignment, but you couldn't just copy their work. She said she was going to give me no credit for the assignment and make sure I don't do it again because plagiarism is a serious offense.

I protested my innocence. She said she was doing me a favor by just giving me no credit on the assignment. She explained that plagiarism was against the school's academic honesty policy and I could be kicked out entirely if I pushed the issue. So I didn't push the issue.

Now, there's certainly plenty of ways somebody could have copied my work... One of the easiest would've been just to grab the printout out of the bin over in the computer lab, and re-type the work as your own.

But there's no way I copied anyone else's work. I did the project entirely on my own, from my dorm room... Hit print... Then went across campus to pick it up and turn it in. I've always been an introvert, so I never sought out group work. And this was an early, low-level, introductory course that wasn't nearly challenging enough to require collaboration.

That haunted me throughout the rest of my college career. I was afraid of leaving printouts unattended, so I'd always print them right from the lab and wait by the desk while they printed. I was paranoid about accusations of plagiarism so I would embed weird little personal comments in weird places in my code, in the hopes that it would be personally-identifying. I disliked group work even more after that accusation, because I knew one of my classmates had copied my work and could've cost me my degree.

Hell, it still bothers me to this day.