Suspect your male coworker makes more than you? Here’s what not to do

Perhaps it was your friend in human resources who revealed your teammate's salary in confidence. Maybe you caught the numbers on his paystub (the one he openly left on his desk.)

Or maybe he just told you how much he makes because he wanted to help.

No matter how it's discovered, learning that your male colleague earns more can feel like a total injustice. It's no secret that women make on average 20 percent less than men. The gap is not always a matter of gender bias, but what if, in your case, there seems to be no other excuse?

I recently interviewed media executive turned startup investor Fran Hauser, whose upcoming book, "The Myth of the Nice Girl: Achieving a Career You Love Without Becoming a Person You Hate," tackles this and many complex workplace issues,

Hauser, herself, recalls that when a female member of her staff approached her having learned that she was earning 20 percent less than a male peer, Hauser quickly upped her staffer's salary to match her male colleague's.

Indeed, our instinct may be to immediately bring this pay gap revelation to the attention of our boss. Wouldn't he or she want to know? And given the current national discussion and changes related to wage discrimination, #timesup, #metoo and workplace inequality, you may feel more empowered than ever to lead with this in your upcoming review. I certainly would.

It used to be bad etiquette to talk about your salary, but now many companies and individuals are using transparency to tackle the issue, says Hauser. Salesforce now conducts salary reviews to ensure pay parity, a Google engineer started a public spreadsheet where employees could post and compare salaries, and at Buffer the company lists staff salaries on its website and shares the formula for how they calculate it.

Hauser agrees that we should be vocal — now more than ever. "These movements are shining a light on the inequality, biases and abuse of power that have existed for a long time. And, unless you speak up, no one will know to do something about it," she says.

But not right away, and definitely not until you have more facts. Here are three more things you shouldn't do (no matter how angry you might be):

Your employer may be in the wrong, but it's still your job to prove it. That may take a little bit of time and more evidence than a paystub or word of mouth. Hauser asked her employee to dig up a few more facts before giving her the raise.

Instead, approach the problem like a lawyer would, says Hauser. Perform an apples-to-apples comparison of all the factors that may go into one's salary negotiation, including years of experience in the industry, time spent with the company, number of direct reports, and responsibilities. Also, did he try to quit and the boss offered him more money to stay? Bottom line: Does your colleague – in any way – bring more value than you do to the company?

If you discover that you're both truly on the same level, then you are, as Hauser says, "in a peer role." And at this point, it's important to approach your boss about the pay gap with all your evidence in tow.

If it's difficult to gather all the facts, you can still have a conversation with your boss about what you've learned, that you want to discuss the reasons why the pay gap exists and that you are interested in earning more.

Play up the fact that your "peer" is earning more than you are, not so much that he's your "male co-worker."

"I don't know if you have to make it about the whole male, female thing," Hauser says. "I think it's just really more about, 'This person is my peer. We're bringing the same experience and qualifications to the table, yet they're making more than me'…It's really hard to argue with facts."

Your demeanor can also help to further your case. Stay direct, confident and positive. "If you approach the conversation in a state of anger, your manager will immediately feel defensive," says Hauser. "That's not productive."

So how do you actually start the conversation? Is there a script? Yes. Hauser has that, too. She suggests you try this:

"I have learned that my salary is not in line with my colleague who shares a similar job to mine. This makes me feel that I'm being undervalued. This is the salary range of people who are doing the same job as me. Given what I've learned, I'd like my compensation to be formally reviewed. I have contributed in these ways and know I can continue to make an impact here. How can we make this work?"

The use of "we" is key here, because it demonstrates empathy, says Hauser. "Present this as a problem you would like to solve together."

Farnoosh Torabi is a CNBC Make It contributor, author and host of the popular financial podcast So Money where she interviews everyone from Tony Robbins to Deepak Chopra to Margaret Cho about their personal spending, saving and investing habits. For more download her free e-book So Money Secrets: Financial Habits of Highly Successful People.

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