Demonstrations began on Friday after Immigration and Customs Enforcement (ICE) raids in heavily Latino parts of the city, by the federal agency that identifies people in the US illegally and carries out arrests and deportations.
Doechii added: "I want y'all to consider what kind of government it appears to be, when every time we exercise our democratic rights to protest, the military is deployed against us."
Last year's BET hip-hop awards were also dominated by Lamar, where he won eight out of 11 nominations.
Ultimate icon awards, for achievement in music, entertainment, advocacy and community impact, were also handed out to musicians Mariah Carey, Snoop Dogg and Kirk Franklin, along with actor Jamie Foxx.
Foxx accepted his award from Stevie Wonder, and spoke about his recovery after having a stroke in 2023.
"I gotta be honest, when I saw the in memoriam [segment], I was like, 'Man, that could have been me'," he said.
Carey, who also performed at the awards, was given hers by Busta Rhymes, and said: "This means so much. If you're gonna get one, might as well start with the Ultimate Icon Award.
"My life and career have been quite the adventure. I will spare you the long, drawn-out saga tonight," she added, as she praised her fellow icon winners.
Wicked star Cynthia Erivo won best actress, having also been nominated for the BET Her award - which recognises empowering songs that focus on women - for her stellar version of Defying Gravity. Gladiator II's veteran star Denzel Washington won best actor.
The ceremony also featured R&B artist Ashanti's compilation of songs, including her 2002 hit Foolish, while Lil Kim performed Left Eye (Remix) with Honey Bxby.
Other performers included Jim Jones, Amerie, Keyshia Cole, Mya, TI, B2K and Bow Wow with Jermaine Dupri.
