13 signs your coworker is a psychopath

Andrew Faas, a former senior executive with Canada's two largest retail organizations, found this out the hard way when he blew the whistle on a corrupt colleague, and subsequently had his phone and email hacked and even received an anonymous death threat.

To help others, Faas says in his new book, " The Bully's Trap," any worker being hired or promoted in a supervisory position should be required to take a psychological test.

What would it test for? The 20 signs listed in the Hare Psychopathy Checklist, as developed by renowned psychologist Robert Hare.

A psychopath may not show all he signs, but they will likely demonstrate at least some of them, Faas says.

Here are 13 sign that one of your coworkers may be a psychopath, from Hare's checklist, Faas, and articles we found on Psychology Today:

Natalie Walters contributed to a previous version of this article.