As the Black Lives Matter movement gains more public attention, there are questions being raised about who's in charge of the movement and what its long-term goals are.

The Black Lives Matter organization traces its roots back to the fatal 2012 shooting of 17-year-old Trayvon Martin, and picked up steam after 18-year-old Michael Brown's death.

Some police are now blaming the increased attention on deaths of unarmed black men for the killing of some police officers. But Black Lives Matter organizers say their cause has nothing to do with police deaths.

Founder Alicia Garza says everyone wearing a "Black Lives Matter" t-shirt or carrying a sign isn't part of the movement. But she says that's a good thing as long as they are working to make black lives matter.