Aug. 28 has always been a special day for me.

Forty-nine years ago on this day, Dr. Martin Luther King Jr. shared his dream with America on the steps of the Lincoln Memorial in Washington, D.C. Forty-seven years ago today, I was born in St. Louis, Missouri. And four years ago today, I celebrated my birthday with my former Harvard Law School classmate Barack Obama as he accepted the Democratic nomination for president at Invesco Field in Denver.

Standing next to me that night in 2008 was another law school classmate, Rep. Artur Davis, who had been a strong and early supporter of Barack Obama. As a member of the House of Representatives, Davis supported President Obama’s agenda 95 percent of the time, according to the Congressional Black Caucus, and he was quoted as saying, “I agree with him on everything."

Just three years ago, Davis chided the GOP as a party that "marches in lockstep, demands the most rigid unity, and articulates no governing philosophy beyond the forceful use of the word 'no.'"

Before that, Davis had called for the resignation of the Bush Administration's Justice Department’s Voting Rights chief after the official claimed that voter ID laws did not hurt minorities. As Davis said at the time, "You can’t argue that voter ID laws don’t disfranchise African-Americans."

But Davis, who represented a Black district in Alabama, wanted to follow in Obama's footsteps by winning statewide office. Davis ran for governor of Alabama and lost the 2010 Democratic primary by a huge 24-point margin (62 percent to 38 percent).

So Davis left Alabama, moved to Virginia, became a Republican, and endorsed the very voting restrictions he had once condemned. Tonight, on the anniversary of Dr. King's most famous speech, Davis will condemn the nation's first Black president at the Republican National Convention in Tampa, where only 46 of the 4,411 delegates and alternates are Black.

As he seeks to win acceptance from a crowd he once disdained, Davis would do well to remember these famous words from Dr. King:

"Cowardice asks the question Is it safe? Expediency asks the question Is it politic? Vanity asks the question Is it popular? But conscience asks the question Is it right? And there comes a time when one must take a position that is neither safe, nor politic, nor popular; but one must take it because it is right."

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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