Matt Rourke / AP

If you've heard of Joseph Kent, you probably only learned his name in the last couple of days. Late Tuesday night, a CNN camera caught a spooky video of Kent being arrested in Baltimore: As Kent walked in the street, a humvee drove between him and the camera, just as a line of police lunged at the young man. Then he wasn't heard from again for 24 hours. Talib Kweli tweeted a demand to know where he was, and Kent's name trended on Twitter. Dark conspiracy theories suggested he'd been kidnapped or disappeared.

It turned out that Kent, a 21-year-old student at Morgan State University in Baltimore, was waiting in a holding cell in the city jail. The facility was so crowded with people swept up by police during unrest that he hadn't been booked, which meant his name wasn't in the jail's system yet and so no one could find him. His attorney, Steve Beatty, was able to locate him Wednesday and to get him released on his own recognizance that night.

Kent is, in fact, more easily recognizable in Baltimore. City Paper, the local alternative weekly, profiled him in November 2014, in a piece about how the aftermath of Michael Brown's shooting in Ferguson, Missouri, was creating a new cohort of civic leaders. Reporter Baynard Woods recounted Kent maintaining peace during a tense situation, near the end of a march in Baltimore protesting a grand jury's decision not to charge Officer Darren Wilson for Michael Brown's death:

"We been peaceful all day, and now everybody want to show your ass," Joseph Kent, a 21-year-old student from Morgan State University, said from the center of the crowd near the end of Tuesday's protests over the grand jury decision in Ferguson, Missouri. "We're not here for that."

Kent says he was again trying to keep the peace when he was arrested Tuesday. His attorney, Steve Beatty, told me on Thursday that the only charge pending was for one count of violating curfew, a misdemeanor. "I've read it a couple times; I don’t even see a penalty in it," he said. Beatty believes the media attention helped Kent get out of jail faster, noting that other people arrested in the protests had their bail set at unusually high levels—$500,000 or $750,000—in contrast to Kent's release on self-recognizance.

"I don’t think he’s ever been arrested before," Beatty said. "He led the charge in keeping the Ferguson protests peaceful." In fact, Kent was back out on the streets Thursday, leading a march from City Hall to the Penn North area.

Kent's role in the marches shows the way that Ferguson has created a new group of leaders across the country dedicated to civil rights and pushing back against police. While the national attention paid to Ferguson was astonishing, critics complained that it was little more than "hashtag activism": People could express their support from the comfortable distance of a computer, retweeting sympathetic messages without ever having to buy in. And once the marches for Michael Brown died down, where would those people go? Would they simply lose interest and move on, leaving the movement to sputter?

One of the most prominent activists to emerge from Ferguson was DeRay McKesson, at the time a school administrator in Minnesota who traveled to Ferguson to take part in protests and was also extremely active in social-media networking. (He has since quit his job and moved to St. Louis.) In an Atlantic interview with Noah Berlatsky, McKesson pushed back on the claim that what was happening was mere hashtag activism.

"What is different about Ferguson, or what is important about Ferguson, is that the movement began with regular people," McKesson said. "There was no Martin, there was no Malcolm, there was no NAACP, it wasn't the Urban League. People came together who didn't necessarily know each other, but knew what they were experiencing was wrong .... And Twitter allowed that to happen."

Even if it just seemed like people chatting online, that effort would pay dividends later, he argued: "Twitter has enabled us to create community. I think the phase we're in is a community-building phase. Yes, we need to address policy, yes, we need to address elections; we need to do all those things. But on the heels of building a strong community."

The marches in Baltimore and elsewhere are at least preliminary vindication of that claim. McKesson, who is from the area and lived in Baltimore for years, has been in the city for the protests. (I contacted him, hoping to speak about this, but haven't heard back yet.) He's given some interviews, including a calm but effective pushback on Wolf Blitzer during an awkward discussion of violence:

As marchers took to the streets of other cities around the nation on Wednesday night, the names of the organizers were familiar as people who have been leading protests since Michael Brown's death. In Boston, Brock Satter organized a march Wednesday night; he previously helped put together a Martin Luther King Day march and a New Year's Eve die-in. Umaara Elliott, a New York teenager who co-organized Millions March NYC in December, was out marching Wednesday as well.

These continuities suggest a real network of organizers around the country who can turn people out into the streets, not just inspire them to retweet. Sadly, there seems to be no end in sight to the deaths of young black men at the hands of the police, which will likely provide plenty of additional tests of the movement's ability to cohere. As for Joseph Kent, his lawyer said he was planning national media interviews for Thursday evening, but his client wasn't as excited about that as he was about getting back out on the protest lines.

"You’d think for a 21-year-old kid, getting on TV would be his priority," Beatty chuckled. Instead, he was out marching. "He remains resolved in his dedication to peaceful protest and he hopes other will follow his lead."

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