Tips by Mira Zaslove
Follow your gut. I've interviewed and hired many people over the years, and generally the ones I didn't like in the interview turned out to be the jerks. Not always, but more often than not, follow your instincts. If someone seems like a jerk, they probably are.
Pay attention to body language. Jerks often do things like: sneer, roll their eyes, clench their fists, and flare their nostrils. Also watch if they sit in a defensive stance or if they aggressively hit the desk with their hands.
Watch how they treat everyone around them -- including the admins, interns, and people they believe won't be involved with judging them. What how they react to Executives and if they appear to be two different people depending upon who they are talking to.
Jerks tend to be arrogant, defensive, and abrasive in the interview -- so watch out for signs of this behavior. If they cut you off, argue or belittle others, that is usually a clue.
Ask the candidate for examples of a situation where they have been competitive, and how other people they have worked with would describe them. Ask for specific examples, and let them talk. Many jerks are proud of their cutthroat behavior. I once had a candidate tell me that they were not a fit for their family business because they hated to be wrong and nobody who really knew them would ever want to work with them.
Ask the candidate what kind of management style they prefer, and how they work as part of a collaborative group.
Be a little careful here though, because some candidates can come off poorly in an interview, when really they are just nervous or poor interviewers. Also many jerks are good interviewers and are prepared for these types of questions, so try to look past their charisma and canned answers.
Get a second and third opinion. People tend to like people like themselves, so have the biggest asshole you know interview them, and see what they think. The biggest jerk I ever hired was hired because the biggest jerk at the entire company lobbied for him....against my recommendation.
Another thing that is often overlooked: don't be an asshole yourself or work in a toxic work environment. People tend to act like the people around them. Companies develop a culture and asfamously said, "we are the average of the five people we spend the most time with."
When it comes to abrasive and competitive behavior in the workplace, people are probably more influenced by the company culture than they are by anything else. Culture comes from the top. So if assholes succeed at your company, it might be tough to screen them out in the interview process.
One of the nicest people I ever hired, turned into a selfish jerk after working in an aggressive environment. Similarly, I've seen real jerks start to act surprisingly polite when they worked under a manager who would not tolerate bad behavior.