(The Root) -- Shortly after it was announced that Rep. Paul Ryan would join the Romney ticket as this year's Republican vice presidential candidate, I wrote a piece titled,  "What We Know About Paul Ryan and Blacks."

Well, I recently learned of another significant addition to this list.

As reported on Twitter by CNN's Pete Hamby, Ryan said he has a black sister-in-law, but perhaps even more interesting, his "college sweetheart" was African American.

So here is the million-dollar question: Is the fact that Ryan has dated interracially a noteworthy detail to consider when analyzing his politics and policies?

Here's a well-known phrase that has virtually become a punch line: When someone finds himself on the ropes facing an allegation of racism, the go-to reflex defense is usually something along the lines of "But some of my best friends are black!" Translation: "I can't possibly be racist or racially insensitive because there are black people I like and they like me. So there." Many of us are so used to hearing this -- and, frankly, dismissing it (remember George Zimmerman's media-friendly pal Joe Oliver?) -- that we long ago stopped asking, What if it's actually true?

For years Lou Dobbs was the face of the anti-illegal-immigration crusade. As a result of his seeming obsession with the issue, he became in the eyes of many the face of xenophobia and racism, not to mention public enemy No. 1 of Mexican immigrants. There's just one hitch to this narrative: Dobbs is married to a Mexican-American woman, meaning that he is the father of Mexican-American children. (His Mexican-born mother-in-law even lives with his family.)

When I discovered this I was surprised, and not for the reasons you may think. While I was somewhat surprised to learn of his wife's heritage, given his own politics on issues that overwhelmingly affect a community of which she is a member, I was even more surprised that I'd never heard him mention it on his program or prominently in interviews. He certainly didn't hide it, but my point is, if anyone could have benefited from a "But my best friend -- in fact, my wife -- is Latina, so I can't be bigot" defense, it was Dobbs, and yet he chose not to hide behind that.

Certainly, having a relationship with someone of a different race does not automatically make someone more racially sensitive and enlightened. Throughout his lifetime, Sen. Strom Thurmond of South Carolina financially and emotionally supported the daughter he fathered with an underage black servant. In addition to paying for her education, he was also known to play the part of proud parent by visiting her college campus and make inquiries to faculty about her educational progress.

Yet at the same time he was doing this in private, he was publicly advancing policies that would have rendered his daughter's education virtually useless. If those policies had succeeded, she and her children, with whom he also maintained a relationship, would have remained second-class citizens. Does this mean that Thurmond's relationship with his daughter was not genuine? From her recollections regarding the lengths he went to in order to remain a part of her life, I doubt it. 

So then, how could he genuinely care for his black daughter and promote policies that would harm African Americans, and therefore harm her? Research has shown that those who hold stereotypes about a particular group of people are unlikely to have those stereotypes altered merely by encountering someone who defies that stereotype. Instead, they are likely to view the individual defying said stereotype as an exception. In other words, it is possible to have a black friend, Asian friend, Hispanic friend or Muslim friend or wife and still exhibit prejudice toward that group. The friend or wife is simply viewed as the exception who is not like the others.

For the record: No, I am not calling Ryan a racist. I am saying, however, that if you want to know where a politician's heart lies when it comes to a particular community, it may be best to look at that person's policies -- such as his or her record on civil rights --  rather than personal relationships. What do you think? Please share your thoughts in the comments below. 

Read more of The Root's coverage of Rep. Paul Ryan here.

Keli Goff is The Root's political correspondent. Follow her on Twitter.

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Keli Goff is The Root's special correspondent. Follow her on Twitter.

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