Everything you need to know about Bill Clinton’s Social Security ID card proposal.

On Wednesday at the Civil Rights Summit in Austin, Texas, former President Bill Clinton mentioned the possibility of turning Social Security cards into photo IDs as a way of counteracting voter suppression. It sparked immediate reaction from the left and the right — it’s the thread of an idea that has provoked controversy many times over the past decade.

Read More: Everything you need to know about Bill Clinton’s Social Security ID card proposal. And why it won’t work..