(VALERY HACHE / Getty Images) (VALERY HACHE / Getty Images)

Celeb: Esperanza Spalding, the genre-defying vocalist and bass player, who performed at the White House in 2009 and won a Grammy for “Best New Artist” in 2011.

Cause:  On Wednesday Spalding joined with top brass from the Center for Constitutional Rights, Human Rights Watch, Amnesty International and the ACLU to host a free concert that included a policy-drenched panel discussion about the prisoners currently held at the Guantanamo Bay Naval Base.

Scene: A packed house at the Lincoln Theatre on U Street almost didn’t notice as the diminutive Spalding strolled onto the stage quietly in a floor-length wrap skirt topped with a black leather bustier.  She was missing her trademark billowing hairstyle. “The afro only comes out when you pay for a ticket,” the singer joked. Spalding performed songs spanning all four of her studio albums before relinquishing the stage to a discussion  led by Van Jones of CNN’s “Crossfire.” Spalding then screened a video for what some dub her “protest song,” “We Are America,” which calls for the closure of the Guantanamo detention center.

Soundbite: “I hope to get you. I hope to move you. I hope to touch you,” said Spalding.