I know I'm a pain about gender and diversity issues, so I don't take it personally when law firms sometimes avoid me like an STD. Sure, they love to tell me about their newest, most awesome diversity initiatives, but if I press them about their track records on female or black equity partners—well, let's just say, they're not so forthcoming.

But I've noticed an exception to this rule. Firms with major labor and employment practices usually chase me down to tout their diversity records. Their spiel is that they're not like the other big firms. It's like they're saying, “See! We have female and black partners! And more than just one or two!”

Indeed, it's no secret that labor and employment is packed with female lawyers (remember, I called it a Pink Ghetto), but is this a practice where black lawyers are prevalent, too? If so, is this one explanation why women and black partners lag behind white male partners in compensation? (Male partners make 53 percent more than female partners, while the earnings gap between white and black partners is 15 percent, according to Major, Lindsey & Africa's partner compensation survey.)

The answers to those question seem to be yes. First, keep in mind that labor and employment partners report the lowest total compensation ($681,000 compared with $1.18 million for corporate partners). And women represented an astounding 38.9 percent of labor and employment partners in the MLA survey (versus only 16.2 percent female corporate partners). Black partners were also more dominant in the labor and employment field, making up 8.4 percent of partners (versus 0.9 percent who identified as corporate partners). Though the sampling in the MLA survey was small (24 partners identified as black, representing 1.9 percent of the 1,246 respondents), “it is a large data set and there is no particular reason to suspect that the 1.9 percent isn't representative of the market overall,” says Lucy Leach, research director of Acritas, which administered the survey. “Another way of looking at it would be that a third—eight of the 24—black partners responding were labor and employment lawyers, compared to 7.9 percent of white partners.”

So here's the big question: Why are women and black partners occupying such a big chunk of the lowest-paid sector of Big Law? I'll ask the same question about black partners that I did about female partners in this area: Are they there by choice? Or are they somehow pushed into the least lucrative, nonglamorous rungs of Big Law?

While women might gravitate toward labor and employment because it provides more predictable hours, I'm doubtful that explanation is relevant to black partners, especially the men.

One former lawyer, who's African-American, says it's easier to elevate black labor and employment lawyers because it doesn't really upset the existing order: “It's rote work, not bet-the-company litigation. Big companies have a lot of small employment matters, where the plaintiffs are often minority, hourly workers. By using minority lawyers, companies can show the board that they have diverse outside counsel and get credit.” Plus, adds this lawyer, many partners in labor and employment are nonequity. “It's a way to throw a bone,” the lawyer says.

That said, no one claims that black lawyers are deliberately steered into certain practices.

“I think it's a matter of choice,” says Bernadette Beekman, managing director at Hire Counsel, a recruiting firm. “That's where they see people of color. A lot of people don't go into certain areas because they don't see anyone like themselves.”

In other words, it's the old chicken/egg thing.  Of course, it's only human nature to gravitate to a group where there's a critical mass of like-minded souls.

But does that qualify as a choice?

Contact Vivia Chen at [email protected]. On Twitter: @lawcareerist.