Sharpton, a Baptist minister, runs the Harlem-based National Action Network, a civil rights organization. He's been a frequent presence as an advocate in racially-charged cases dating back to Tawana Brawley's accusations of an assault that turned out to be a hoax in the late 1980s.
He joined MSNBC's roster of hosts last summer after extensive discussions about how his activist role would continue while on the air.
MSNBC chief executive Phil Griffin said his chief requirement was that Sharpton discuss his activism with network bosses so they could decide, on a case-by-case basis, how it would affect "Politics Daily," which begins at 6 p.m. ET.
"We didn't hire Al to become a neutered kind of news presenter," Griffin said. "That's not what we do."
Griffin, talking before Monday's show, said he hadn't seen any conflict with Sharpton's role on and off the air in the Martin case. He said Sharpton had fulfilled his requirement to honest and upfront about his activities, and credited "Politics Daily" with helping to make it a national story.
Eric Deggans, a media critic for the Tampa Bay Times who has discussed Sharpton's role on CNN's "Reliable Sources" and elsewhere, recalled being treated like he was "nitpicking" last August when he first raised questions that Sharpton's activism could present conflicts for MSNBC.