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Larissa (not her real name) was partying with coworkers and subordinates outside of work. There was a lot of drinking and things got out of hand. People started arguing and a fight broke out.

Intoxication impaired Larissa's judgement. She added fuel to the fire by choosing sides and gossiping.

There was fallout the next day at work. Employees were upset about the altercation and angry at Larissa for her role in it. After all, Larissa was a manager and someone people expected to be a voice of reason.

Her boss quickly got wind of the story and had to investigate.

Larissa admitted her role in the fracas, but didn't accept responsibility. She felt that what she did on her own time was her own business, without understanding that a manager drinking with employees can still be considered a work function.

Her boss subsequently learned that Larissa had created issues at her last job. None of that surfaced during the interview process because Larissa's references had lied about her qualifications and conduct.

Avoiding toxic employees like Larissa can be tricky. In a surprising revelation, many common hiring practices actually attract toxic workers. Here's how to avoid that.

How common are toxic employees?

Michael Housman and Dylan Minor conducted a study of toxic employees in 2015. They reviewed 58,542 customer service employees from multiple companies and found that 1 in 20 were fired for toxic behavior within their first year of employment.

Toxic behavior is defined in the study as "an egregious violation of company policy. Examples include sexual harassment, workplace violence, falsifying documents, fraud, and general workplace misconduct."

It makes sense to avoid hiring toxic people, but that's easier said than done. Larissa got hired by getting references to lie on her behalf and falsifying her resume (more on that in a moment). 

So how can you spot a potentially toxic employee? The study highlighted three specific factors to look for. 

How can you screen out toxic people?

The study identified three prominent risk factors for toxic behavior:

• Overconfidence

• Self-regarding

• Rule-orientation

Let's take a closer look at each one, starting with overconfidence. 

Overconfidence

These are employees who believe they're awesome, even when they're not. 

Study participants were asked during the interview process to estimate their level of computer skills. The applicants were later given a skill assessment to determine their actual skill level.

A whopping 34 percent were overconfident, with the skill test revealing they were less skillful than they had claimed. These employees were 15 percent more likely to be terminated for toxic behavior than the rest.

I've run my own experiments that reveal customer service employees consistently overrate their abilities. These overconfident employees are less likely to accept feedback, learn new skills, or improve their performance because they don't believe they need to.

One of the warning signs Larissa's boss missed during the initial interview process was Larissa lied on her resume. She overstated her qualifications and was overly confident about her ability to do the job. 

You can avoid hiring overconfident employees by having them demonstrate their abilities during the selection process whenever possible. This might include a computer test or asking them to write a sample customer email.

Some abilities, like defusing an angry customer, are more difficult to test in an interview. One solution is to ask candidates to relate a specific experience rather than respond to a hypothetical situation. So you might ask, "What happened the last time you had to defuse an angry customer?"

Janis Whitaker's excellent book, Interviewing by Example, provides lots of great examples and ideas for crafting these types of interview questions.

Self-Regarding

Pop quiz. What type of person do you think is generally better at customer service?

1. Someone who is self-centered

2. Someone who cares deeply about others

If you answered "someone who cares about others," you're right. The study found that self-centered, or self-regarding, employees were 22 percent more likely to be terminated for toxic behavior.

Recall that Larissa focused on her desire to party and have a good time with friends, rather than her responsibility to be a good role-model when socializing with subordinates outside of work.

Many customer service leaders make the mistake of designing a selection process that attracts people who are more self-regarding.

• Including self-centered terms like "rockstar" or "superstar" in the job posting.

• Promoting perks like games, incentives, and prizes for top performers.

• Selling candidates on advancement opportunities, rather than the job itself.

The way to fix this issue is by emphasizing teamwork and company culture in the interview process. Here are just a few ways to do this:

• Highlight culture on your career page, such as this one from Squarespace.

• Use team-focused descriptions in job postings.

• Screen candidates for culture fit using this guide.

Above all, do away with contests, games, and prizes that promote self-regarding behavior. There's extensive research that proves incentives can crush an employee's motivation to do the right thing.

Rule-Orientation

Job applicants in the study were asked to decide which of two statements most applies to them.

1. I believe rules are made to be followed.

2. Sometimes it's necessary to break the rules to accomplish something.

The surprising twist is people who chose "I believe rules are made to be followed" were 25 percent more likely to be fired for toxic behavior. It seems that someone stating they are a rule-abider doesn’t necessarily mean they’ll actually abide.

Customer service managers with a lot of toxic employees tend to be overly focused on rules.

• Attendance policies

• Dress codes

• Conduct policies, such as the use of personal cell phones

The solution to this challenge can be counterintuitive. Customer-focused leaders spend less time on rules (what not to do), and more time reinforcing positive behaviors (what to do).

For example, rather than reviewing the attendance policy with an applicant, a customer-focused leader might emphasize why an employee might want to come to work every day. Perhaps the company offers fun and challenging work, has a compelling customer service vision, and creates an environment where coworkers genuinely trust and support each other.

Take Action

Hiring good, non-toxic employees is difficult.

When I wrote about customer-focused companies in The Service Culture Handbook, the chapter on hiring was the most difficult to write. There were too few companies that did a fantastic job recruiting the right people.

You can make strides by avoiding overconfident, self-regarding, and rule-oriented job applicants. I've also created this hiring resource page to give you more tools and information.