The last time I saw Artur Davis, it was on my birthday in 2008.

He was standing just a few feet away from me at Invesco Field in Denver next to the press risers on the field. I was covering the convention as a TV correspondent for BET that year, and I was excited to be a witness to history.

It was the night when Barack Obama was accepting the Democratic Party nomination for the presidency. Davis and I attended law school together, along with Obama, so it should have been a moment of great pride for both of us. But instead I felt an awkward sense of distance with the congressman that evening.

When Davis left his seat in Congress representing Alabama to run for governor in 2010, another one of our Harvard classmates, Terri Sewell, ran for Davis's seat in the majority-black district. I was elated when she won. Terri Sewell is everything Artur Davis was not. Most importantly, she is a woman of the people, dedicating herself to the interests of her constituents instead of selling them out as part of an ambitious political agenda for higher office.

Sadly, Congressman Artur Davis sold out his own constituents for his own personal gain. Among his many transgressions, he was the only member of the Congressional Black Caucus to vote against health-care reform, even though he represented a district that was not exactly wealthy in one of the poorest states in the union.

People in Davis's district would benefit directly from provisions in the president's health-care law that would make health-care coverage more affordable and portable and ban insurance companies from discriminating against people with pre-existing conditions. But Davis wanted to run for governor, and health-care reform was not too popular outside of his district in that conservative southern state.

Davis also voted against the 2007 Employment Non Discrimination Act and the 2009 Hate Crimes Prevention Act. Once again, he was the only member of the Congressional Black Caucus to do so. Who would imagine that a black Democratic member of Congress from the state of Alabama, of all places, would vote against a federal hate crimes law?

Alabama was the cradle of the civil rights movement. It was the state where Rosa Parks was arrested for refusing to give up her seat to a white man, and where African-Americans formed car pools and walked to work to boycott the Montgomery bus system for more than a year.

Alabama was the state where segregationist Gov. George Wallace literally stood in the schoolhouse door to block Black students from enrolling at the flagship university. It's the state where churches were bombed, where vicious police dogs were let loose on school kids and Dr. Martin Luther King Jr. was thrown in jail.

But Artur Davis wanted to be governor.

When the voters in the Alabama Democratic primary rejected Davis in his gubernatorial campaign, he left the state and moved to Virginia. Then this week Davis acknowledged that he has also left the Democratic Party and become a Republican, complaining that the Obama administration "punishes businesses and job creators with more taxes." And now Davis is considering a run for the Senate in Virginia. He's even out stumping for conservative voter suppression laws that make it more difficult for Blacks and Latinos to vote.

I don't know if Artur Davis was ever really a Democrat. Maybe he was and got frustrated. Or maybe the green-eyed monster of envy and ambition convinced him that white southerners would like him more if he became a docile, obedient Negro Republican willing to be their new token Black.

Whatever the case, I won't miss Artur Davis, and I'm sure most Black Democrats won't miss him either. But even after abandoning the Black community, what Davis doesn't seem to understand is that the white people he wants to woo so badly probably won't vote for him either. Putting naked ambition ahead of your constituents' interests is not a good strategy to win new voters of any race.

So goodbye Artur Davis. I hope you come to your senses one day. But until you do, good riddance.

Keith Boykin is a New York Times best-selling author and former White House aide to President Clinton. He attended Harvard Law School with President Barack Obama and currently serves as a TV political commentator. He writes political commentary for BET.com each week.

The opinions expressed here do not necessarily reflect those of BET Networks.

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