NEW YORK (MainStreet) — They may seem normal, diligent and affable, but when it comes to new employees remember that crazy can fool you for a little while. Keep an eye out for these red flags, or you could end up hiring a psychopath:

What to look for on a resume

If a candidate has been through six jobs in the past 10 years, that’s not normal, says clinical psychologist Barbara Greenberg. Don’t try to convince yourself that “this time will be different” — it won’t be.

“They have a pattern of job hopping and they have no respect for the investment that companies have made to train them,” she says. “No matter how bad a job is, people who care about their careers give it at least a year, maybe two.”

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When a candidate can’t hold jobs for longer than 12 months, it’s a sign that they either can’t do the job due inability or poor work ethic, or that they don’t get along well with people. No matter the case, run far, run fast, Greenberg says.

“They think the rules don’t apply to them. Maybe they can’t show up on time. Maybe they disappear every day for three-hour lunch breaks,” she says. “They’re the kind of person who you can’t get through to and you can’t depend on.”

If a candidate has unexplained gaps on their resume or claims that they were laid off in a “mass layoff,” do a little digging, says Tom Gimbel, founder and CEO of LaSalle Network, a Chicago staffing and recruiting firm. For starters, ask about the other jobs in their department that were eliminated.

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“If people on their team were let go, did they all have the same title?  Did they have a teammate at relatively the same level who wasn’t let go?” Gimbel asks. “It’s easy for people to get defensive and not own up to the fact that they were let go for their skills. Introspective candidates, however, acknowledge this and do something post-layoff to ensure it doesn’t happen again.”

Rather than having been laid off, the candidate may have been fired, Greenberg says.

“It may be that they couldn’t perform under pressure, and when the going got tough, they just left. In many cases, people just aren’t willing to stick it out and learn.”

On any resume, pay close attention to the candidate’s references. If they’ve had five jobs but list references from only one or two companies, rest assured some bridges were burned.

What to listen for in a reference:

It’s counter-intuitive, but if a reference is too glowing, that’s cause for concern.

“If everything that a reference has to say about a candidate is 100% positive, then it’s probably not authentic,” Greenberg says. “All that’s glittering isn’t gold.”

References that are too dazzling may indicate you have a narcissist on your hands. They are excellent charmers.

“Psychopaths are very good at charming acquaintances and colleagues. Narcissists have the ability to be unusually ingratiating. If the reference letter says, ‘This person is the best person ever,’ then that person may just be believing that facade they’re seeing.”

Likewise, lukewarm references may indicate that the referrer is just glad to be getting rid of the candidate. This type of reference won’t appear negative at first glance — it just won’t say much of anything at all.

“They read like, ‘I don’t want to be doing this but I have to be doing this,’” Greenberg says. “There will be very little enthusiasm or substance there. When you read it, you get the sense that the person just wrote it out of obligation and wanted to be done with it as soon as possible.”

A good reference, Greenberg says, should never be over the top or too subdued.

“It should make you feel good after you read it.”

No matter what kind of written reference you get, always follow up with a phone call. You’ll learn much more from a one-on-one chat with someone than you will from what they write.

“People tend to be a little more straightforward on the phone,” she says. “If they do have something negative to say, they’re not going to want to leave a paper trail. It’s risky in this age of litigation. Even if they don’t say anything overtly negative, sometimes you can tell in their tone how they really felt about the person. You’re just looking for subtleties that wouldn’t be in a letter.”

What to watch for in person

If a candidate can’t stop talking about themselves, be careful, Greenberg says. Although this may sound like a no-brainer, most interviews require that candidates offer up some personal details. Worry when they won’t shut up.

“Someone who really wants to be a member of a team will ask questions, not talk about themselves,” she says. “If they sit there just blowing their own horn for an hour, there are some serious personality issues.”

Likewise, if a candidate openly blames his or her previous employers for a lack of career advancement, watch out, Gimbel says. For example, if they say, “I wasn’t given enough responsibility,” ask them if they ever stepped up to take on additional challenges.

“If so, why weren’t they given it? Did they take any courses to build on their skillset? What did they do to expand their own responsibilities? If the answer is ‘nothing,’ then this may be an indicator that the candidate is lazy. This may serve as a preview of the type of work ethic they will bring to your team.”

Also, if the first thing a candidate does when they walk into a room with you is compliment your clothing, your perfume or your office decor, pay close attention to their tactics. You may be seeing their propensity for “slimy, inauthentic behavior,” Greenberg says.

“They’re just manipulating you, and you don’t want to hire a manipulator. They’re just trying to fill in the conversation because they don’t have anything substantive to say.”

In other words, if you ask them about their experience with project management and they start talking about your wonderful taste in shoes instead, get out while you still can.

“They’re more interested in pleasing you than actually doing the job,” she says. “This is a dead giveaway that you’re dealing with an unstable person who didn’t do their homework and now has no idea how to handle themselves in an interview.”

By Kathryn Tuggle for MainStreet

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