With a decision by a Ferguson, Missouri, grand jury believed to be imminent, Attorney General Eric Holder is exhorting police across the nation to prepare appropriately for demonstrations and “minimize needless confrontation” with protesters.

He also says in a video post by the Justice Department that protests are most effective when they’re nonviolent.

The Holder video released by Justice Friday doesn’t specifically refer to the situation in Missouri where a St. Louis County grand jury is deliberating whether to indict police officer Darren Wilson in the Aug. 9 shooting of Michael Brown, an unarmed black 18-year-old.

But in message, Holder does mention demonstrations over the past few months that sought to draw attention to “real and significant underlying issues involving police practices.”

(AP)