Heather Mac Donald, author of the just-published War On Cops, has a message for San Francisco 49ers quarterback Colin Kaepernick: “Get your facts straight.”

She says she’ll leave it to sports fans to decide the propriety of Kaepernick’s refusal to stand for the National Anthem in protest of alleged bad behavior by police. But, she says, “if you’re going to do that, at least make sure you understand this issue.”