Disclaimer: not in US.
Apparently his co-worker unknowingly broke a clause in a contract and the company wanted to penalize him by deducting 400$ out of his monthly salary (minimum salary here is 230$ a month). Granted deducting from salary is illegal in my country you can only deduct from a bonus or something like that. and so he didn't think much about it, but during pay day he noticed that they actually followed through with removing that sum and went to H.R who told him that he had '17 days of absence', and that it was a way to deduct from his salary without having legal action. He did try to amass witnesses to prove he didn't miss 17 work days but people didn't want to speak out of self preservation. He advised that we always record conversations with H.R