“I never saw him, I never met him.”

It took only seconds to utter those words, only seconds to challenge Bernie Sanders’s commitment to social justice and claims that he was deeply involved in the civil rights movement.

The salvo didn’t just come from anyone. It came from Congressman John Lewis, who has represented Georgia’s 5th District since his election in 1986 and is a venerated foot soldier of Dr. Martin L. King Jr. Lewis, along with five others, is a member of “The Big Six”—men who marched shoulder-to-shoulder with King.

While many found Lewis’s remarks unfair and harsh, they opened a very real conversation about how issues specific to our community are prioritized. The fact is, progressives often rely on African-American voters to win primaries and turnout levels can be critical in some general elections. What we do (or don’t do) determines who holds the keys to the White House.

The consistent grievance is that very little has been gained from such support and that black issues—including questions of racial disparities—often take a backseat to economic inequality. Others, including Sanders, attempt to advance the false argument that if you solve the wealth gap then you answer racial disparities.

Sanders, who represents a predominantly white state, has frankly never had to answer to black voters writ large. And, as such, his legislative record is reflective of a man who did not need to be concerned about how people of color were getting along in places like Ferguson, Baltimore, or Flint.

Voting against the Brady Handgun Violence Prevention Act (known as the Brady Bill), failing to support background checks, and being in favor of civil immunity for gun manufacturers likely played well in Vermont, where gun violence is comparatively minimal. His support for the controversial 1994 crime bill—signed by Bill Clinton and supported by Hillary Clinton, and which resulted in the mass incarceration of black men and fueled the school-to-prison pipeline—went unchallenged in Burlington.

When Lewis, a civil rights icon, stepped to a microphone Thursday and appeared to upend the veracity of Sanders’s history of fighting for social justice, white progressives were incensed. Lewis, who was chairman of the Student Nonviolent Coordinating Committee for three years in the early 1960s, said he never encountered Sanders. However, the Vermont senator was a student at the University of Chicago on the city’s southside and he says he was involved in both the Congress on Racial Equality and SNCC. Sanders was indeed arrested during an anti-segregation protest in Chicago.

But Lewis wasn’t only challenging where Sanders was in 196os, he was implicitly challenging where he has been ever since. After Thursday’s press conference, campaign loyalists unleashed a torrent of vitriol.

They called Lewis a liar and an Uncle Tom.

“Maybe if he weren’t selling out the African-American cause for a power position with Hillary?” tweeted David Morant.

A woman tweeting under @PoliticsPeach said, “John Lewis can go 2 hell, he’s not God & he’s also a damn LIAR, now what?”

And it wasn’t just progressives who piled on.

“Meh! John Lewis is race hustler. He isn’t fit to carry MLK’s jock strap,” RINO Hunter opined.

However, when asked to supply specific policies and legislation that Sanders has sponsored, championed or passed, most fell silent or deflected to prosecuting Hillary Clinton’s record. Others took issue with the Congressional Black Caucus PAC. Several progressive journalists, including David Sirota, attempted to discredit the political action committee’s endorsement.

“CBC PAC backing Clinton is run by lobbyists & funded by drug companies, Walmart & Goldman Sachs,” he tweeted, along with a link to an “investigative” story.

It is worth noting that Sirota, who is now editor-in-chief at Political Capitol, is a former Sanders staffer.

Questions about Sanders’s involvement in civil rights-era demonstrations, as well as his proximity to Dr. King himself, first surfaced in the hours after his speech was interrupted at a conference last summer. Sanders was visibly frustrated when #BlackLivesMatter activists prevented him from speaking at NetRoots Nation. His supporters immediately took to social media and began chiding young black activists.

Tyson Manaker called Sanders “one of the first #BlackLivesMatter activists,” citing his involvement in 1962.

The black activists fought back with the hashtag #BernieSoBlack, which exploded with jeering comments and trended for the next 24 hours without pause. The incident caused the campaign to engineer a re-set of its African-American outreach. A black woman now serves as national press secretary and Sanders has been openly courting and successfully recruiting key African-American leaders into his camp.

Certainly, Clinton has many hard questions to answer about her own record on the issues confronting black America. But does that mean that Sanders should be universally let off the hook, because he was among the crowd watching Dr. King speak in Washington?