Protesters disrupt Bernie Sanders, Martin O'Malley

Civil-rights protesters gave Democratic presidential contenders Bernie Sanders and Martin O'Malley a raucous and tense reception Saturday in downtown Phoenix, disrupting and commandeering a forum that was billed as a conversation with the two progressive candidates.

Sanders, a left-leaning independent U.S. senator from Vermont, was visibly irritated at times during his shorter-than-expected appearance at the Netroots Nation gathering. He, in turn, angered the "Black Lives Matter" protesters by not immediately responding to them.

The hashtag #BlackLivesMatter is widely used on social media by activists and their allies.

"Black lives, of course, matter," Sanders said at one point. "... But if you don't want me to be here, that's O.K."

O'Malley, a former Maryland governor and Baltimore mayor whose record has come under fire in the wake of the civil unrest in the city that followed the death of Freddie Gray in police custody, spoke first. He stood by silently on stage as the demonstrators took control of the proceedings.

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"What side are you on, my people," the several dozen protesters chanted as they filed between tables to the front of the Phoenix Convention Center hall, where O'Malley and moderator Jose Antonio Vargas were talking.

Netroots Nation is an annual national gathering of political progressives.

During the event, O'Malley defended his Baltimore law-enforcement legacy.

"Far from bringing forward the mass arrest/mass incarceration policing that you talked about it, I actually made policing more responsive," O'Malley said. "We did a hundred reverse-integrity stings a year."

But O'Malley was later booed when he said: "Every life matters ... Black lives matter. White lives matter. All lives matter."

"The presidential candidates' responses today to the powerful protest led by Black activists at Netroots Nations — as well as other remarks from the campaign trail in recent weeks — make clear that all Democratic candidates have work to do in understanding and addressing the movement for Black lives," said Anna Galland, executive director of the liberal group MoveOn.org Civil Action. "Saying that 'all lives matter' or 'white lives matter' immediately after saying 'Black lives matter' minimizes and draws attention away from the specific, distinct ways in which Black lives have been devalued by our society and in which Black people have been subject to state and other violence."

Kerlyn Bradley, a student from Tucson, was "disgusted" with how O'Malley and Sanders responded to protesters.

"Senator Sanders told us to wait. ... That's what marginalized people have been told to do and nothing's happened," Bradley said after the event.

Tia Oso, a Phoenix resident with the Black Alliance for Just Immigration, said she helped organize the protest because Black-rights issues were not represented at Netroots Nation this year. While events for Latino immigrants were integrated into the convention, black immigrants were ignored, she said.

"We had to do this," she said. "This is the most important progressive gathering."

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In a black shirt with white lettering that said "Black love," Oso got on stage with O'Malley to talk about racial inequality and law enforcement treatment of the Black population and to chide Netroots Nation's programming for not addressing Black immigration issues, such as the Black refugees in Arizona who had to seek asylum because of U.S. foreign policy.

"I feel like his response is very rooted in what he believed his track record was," she said of O'Malley. "He's very tone deaf to our community."

While on-stage, Oso also hammered the Republican-controlled Arizona Legislature and recalled former GOP Gov. Evan Mecham's controversial repeal of the state's Martin Luther King holiday in the 1980s.

Other protesters agreed Netroots Nation did not do enough to address Black issues.

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"They said, 'Oh we're doing it in Arizona. We have to be all about immigration,'" said Angela Peoples, a co-director at LGBT inequality group Get Equal from Maryland. "But then they're only centering the conversation on Latinos, which is important, but we also know that the experiences ... are connected and we need people to be connected to Black lives as much as brown lives."

In a written statement, Netroots Nation said it "stands in solidarity with all people seeking human rights."

"Although we wish the candidates had more time to respond to the issues, what happened today is reflective of an urgent moment that America is facing today," the statement said. "In 2016, we're heading to St. Louis. We plan to work with activists there just as we did in Phoenix with local leaders, including the #BlackLivesMatter movement, to amplify issues like racial profiling and police brutality in a major way.

"It is necessary and vital to continue this conversation. We look forward to doing so in the coming year."

In the chaotic atmosphere, Sanders, who had many fans in the Netroots Nation audience, struggled to make his points about income inequality, the minimum wage and his other top issues.

Sanders drew cheers when he vowed to repeal the Supreme Court's "Citizens United" decision that opened up the floodgates of money into national politics.

"Any nominee I make to the Supreme Court will have to pass a litmus test, and that litmus test is: Overturn 'Citzens United,'" Sanders said.

Vargas, the moderator, asked Sanders about his vote against the 2006 McCain-Kennedy immigration reform bill and how he can reconcile his support for immigrants with his support for organized labor. Sanders countered by asking Vargas why the U.S. Chamber of Commerce and other big-money business interests so badly want immigration reform and, specifically, a new program that would bring low-wage foreign workers into the country.

"Do you think they're staying up nights worried about undocumented workers in this country?" said Sanders, who voted in favor of the more recent 2013 immigration package that passed the Senate with bipartisan support but ultimately did not become law.

For his part, O'Malley was kept on the defensive about police issues for most of his appearance. He said his criminal-justice plan will be forthcoming from his campaign.

"Specifically, I believe every police department in America should have to report, in an open and transparent and timely way all police-involved shootings, all discourtesy complaints and all brutality complaints," O'Malley said when the Q&A resumed after the interruption. "I believe that all departments should have civilian review boards. We implemented one, and it works. But they have to be staffed."

Former Secretary of State Hillary Clinton, the Democratic presidential front-runner, did not attend Netroots Nation. Her campaign cited scheduling conflicts and commitments to speak to Democrats in Iowa and Arkansas.

Republic reporter Madeleine Winer contributed to this article.

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