3 Toxic Employees You Need to Fire NowIf you can't correct their bad behavior, there are three types of employees that have to go.

From a thoughtfulhiring processto a thorough training program, you've done everything you can to find and prepare the best employees for your company. But no system is foolproof and sometimes a few bad apples can slip through the cracks.

Of course, some people just need a simple redirect to fall in line, so trying to correct the behavior should be your first step. But other times, employees can be so toxic, they can poison your workplace, sayshuman resourcesconsultant Suzanne Benoit, founder of Portland, Maine-based Benoit Consulting Services.

"You can have someone who is a very good technical performer but that makes other people in the office go home crying," Benoit says. "If you have people who are interfering with the performance of others, you need to consider letting them go."

It's a good idea to consult legal counsel before you terminate someone for their behavior to ensure you've protected yourself. But, in her experience, Benoit says these three types of employees usually just have to go.

1. The Untouchable
If someone has made him or herself "invaluable" or closely aligned with a powerful person within the company and is using that position to bully others or get preferential treatment, the situation can be damaging to your business, Benoit says. She's even seen situations where the company owner has relinquished so much control to an assistant or subordinate that he or she is afraid to let that person go.

Perhaps your assistant is stepping over the line with his authority or a junior salesperson whose mentor is your top performer is ordering others around. If you see this kind of behavior or you sense bad blood between employees, it's probably time to investigate the source.

Related:4 Ways to Keep Employees From Checking Out on the Job

2. The Pot-Stirrer
This is the person who pits office mate against office mate using gossip, rumor and innuendo. The Pot-Stirrer can usually be found at the center of any office drama, possibly with popcorn in hand. And while the arguments may seem like petty nonsense, this person is causing repeated disruptions in the workplace and costing you productivity and employee engagement.

When there is repeated discord in your office, keep an eye out for the person who seems to be orchestrating it -- perhaps trying to act as an intermediary or even "confiding" in you about various events going on around the office to try to get you involved. Then, have a frank discussion with that person about your expectations about how people behave in the office. If that doesn't work, it might be time for a pink slip.

3. The Renegade
Despite training and repeated correction, this person just doesn't follow rules and puts your company at risk. Whether it's not wearing a helmet on construction sites to "winging it" in customer service matters and making decisions that he or she is not authorized to make, Renegades are determined to do things their way.

The fallout could range from lost customers to safety hazards. And, worse, when other employees see that not everyone has to follow the rules, you may find yourself with more Renegades. Lay down the law or them free.

Related:What It Takes to Be a Boss Every Employee Loves