During a campaign event in Danville, Virginia on Tuesday, Vice President Joe Biden took Mitt Romney to task for his promise to repeal Dodd-Frank Wall Street regulations. “He’s gonna let the big banks once again write their own rules. Unchain Wall Street,” Biden told the majority black crowd. “They gonna put y’all back in chains.”

The outrage from the Romney campaign over Biden’s remark was immediate, but its most calculated hit came from one of the president’s old friends and political allies, former Congressman Artur Davis (D-AL). Now a Republican, Davis had spent part of the day campaigning for Romney in Arlington, Virginia before describing the vice president’s comments as “racial viciousness” in an interview with Wolf Blitzer on CNN’s The Situation Room.

Related:

“I happen to have spoken to a few African-American audiences in my time, represented a predominantly African-American district,” Davis said. “I know what Joe Biden was doing yesterday, and every black person in the room knew who the y’all was, they knew what the chains were about, and they knew what the metaphor was.”

Davis’ willingness to jump into the racial fray and castigate his former friend on behalf of Team Romney comes as the GOP has tapped him for a speaking slot at the Republican National Convention, which kicks off on August 27th in Tampa, Florida. Davis said he plans to speak on Obama’s failure to fix the economy and unify the country.

Four years earlier, Davis was one of the first members of congress to endorse Obama’s presidential campaign. He served as a national co-chair and seconded his nomination at the Democratic National Convention in Denver. However, in his quest to become the first black governor in the bright red state, Davis began moving to the right early in the president’s term.

He attempted to build a broad coalition for the general election by voting against healthcare reform and snubbing the state’s major black political groups. In the process, he turned off many of the black supporters he would need to win the primary. The heavily black electorate responded by nominating Ron Sparks, the state’s white agriculture commissioner, by more than 25 points.

Following his defeat, Davis relocated to Virginia, declared himself an independent and almost immediately became a critic of the Democratic Party, including coming out in support of voter ID laws. On May 30th, he announced on his website that he was officially leaving the Democratic Party to become a Republican.

“Wearing a Democratic label no longer matches what I know about my country and its possibilities,” Davis wrote at the time.

Wednesday on CNN, he said that the Obama administration has gone too far to the left and described Biden’s speech as a divisive tactic that is insulting to African-Americans. “It ought to embarrass President Obama,” he said. “President Obama has talked so movingly about our country moving beyond race, and his own vice president makes this kind of comment yesterday?”

Davis’ concern about racial undertones in the campaign did not prompt him to speak out against Newt Gingrich for calling Obama “the food stamp president” or Romney when he implied that he was booed at the NAACP convention because they wanted “free stuff.”

For his part, Obama has not expressed embarrassment or regret over Biden’s comment. In an interview with People magazine, he defended Biden and tried to put the vice president’s words in the proper context.