Start with high-confidence civil rights books, then narrow by subgenre or adjacent topics.
The Soul of America
Jon Meacham
An Inconvenient Cop
Edwin Raymond, Jon Sternfeld
Confederacy of Silence
Richard Rubin
Shattered Dreams, Infinite Hope
Brandon M. Terry
Nothing Personal
James Baldwin, Eddie S. Glaude Jr.
Everybody's Protest Novel
James Baldwin
Black Marxism, Revised and Updated Third Edition
Cedric J. Robinson, Robin D.G. Kelley - foreword
Freedom Is a Constant Struggle
Angela Y. Davis, Frank Barat
The Rights of Man
Thomas Paine
The Afterlife of Malcolm X
Mark Whitaker, David Sadzin
Bodies of Others
Naomi Wolf