Will musicians answer Questlove's call to fight police violence with music?

"I urge and challenge musicians and artists alike to push themselves to be a voice of the times that we live in," implored The Roots frontman Questlove in a passionate Instagram post earlier this month. It was December 4, one day after a Staten Island grand jury ruled not to indict the police officer whose chokehold ended Eric Garner's life. He continued:

We need new Dylans. New Public Enemys. New Simones. New De La Roachas. Protest songs don't have to be boring or non danceable or ready made for the next Olympics. They just have to speak truth…But my soul is aching man. Seriously just ONE or Two songs that change the course.

So who are the Bob Dylans and Public Enemies of today? Here are four artists with powerful responses to police brutality and the tragic deaths of Michael Brown and Eric Garner.

[Warning to parents and teachers: Some songs contain profanity.]

1. Hip-hop artist and songwriter J. Cole released his passionate Ferguson-inspired track, “Be Free,” on SoundCloud in August with the following message:

Rest in Peace to Michael Brown and to every young black man murdered in America, whether by the hands of white or black. I pray that one day the world will be filled with peace and rid of injustice. Only then will we all Be Free – Cole

The track has garnered over 2.4 million SoundCloud plays, while the full album, 2014 Forest Hills Drive, accumulated 15.7 million streams on Spotify in its first week, surpassing One Direction's first-week record. "Be Free," which features audio from a witness to Michael Brown's shooting, ties Brown's death back to underlying race issues in the US:

When brothers back home be dreadin' when the seasons change

cause they ain’t got no heat and they ain’t got no AC

Walmart Distribution fired my homie, he just had a baby

You wonder why there’s been so many B & E’s lately

2. R&B singer-songwriter D'Angelo thrilled fans by releasing a politically charged album, Black Messiah, after a 14-year hiatus last week. At its release party, D'Angelo said the album is "about people rising up in Ferguson and in Egypt and in Occupy Wall Street and in every place where a community has had enough and decides to make change happen." On “The Charade," he expresses his frustration with racial violence and media portrayal: "Relegated to savages bound by the way of the deceivers/ So anchors be sure that you're sure we ain't no amateurs."

Black Messiah, which has been called "devastatingly great" and compared to Sly And The Family Stone’s There’s A Riot Goin’ On and Marvin Gaye's What’s Going On, might just be the protest music desired by Questlove, who introduced the album at its release party. Spike Lee and music critic Nelson George are among the album's other outspoken fans.

3. Tink, a 19-year-old singer-rapper from Chicago, released the track "Tell the Children" the day after the Michael Brown grand jury decision. She raps about the fear and violence people of color continue to face nearly 50 years after Martin Luther King Jr.'s assassination, while her haunting chorus warns children to watch out because "A badge is a pass to do whatever/ So now we living in fear of the people here to protect us."

4. Run The Jewels 2, the second collaboration of Killer Mike and El-P, features "Early," a powerful track about police violence. Killer Mike (his name is derived from "killing microphones") has long been outspoken about violence, racism, poverty, and other injustices, both in his music and personal life: He wrote an op-ed about Michael Brown's death last summer, and recently discussed his reaction to the grand jury decision on CNN.

In "Early," Killer Mike raps about being harassed by cops in front of his family, adding: "They’ll watch you walk to the store they’re recording/ But didn’t record cop when he shot, no warning."

Read Questlove's full post below, and let us know what protest songs you're listening to in the comments.

By Katie Rose Quandt

This post first appeared on BillMoyers.com.