Lenard Tillery III did not know Alton Sterling well, but the running back had interacted with the salesman who set up shop outside the Triple S Food Mart on North Foster Drive. Sterling invited conversation about his inventory, usually opening with a joke. The 22-year-old Tillery had purchased CDs from him.

Tillery saw the first video of Sterling, a 37-year-old black man with five children, being killed by their hometown police officers, on Facebook. This looks bad, he thought. Man, are you serious?

He had heard about it happening somewhere else because it always happened somewhere else—to Trayvon Martin and Eric Garner to Michael Brown and Tamir Rice and Walter Scott and Sandra Bland and on and on and on. He thought it would never happen here, in Baton Rouge.

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