Verify: Are hundreds of thousands of non-U.S. citizens voting in CA elections?

A viral post on social media claims that last year 449,000 Californians received a jury summons on which they marked the box – I am not a citizen; therefore, I cannot sit on a jury.”
Published: 7:03 AM PDT August 30, 2019
Updated: 7:03 AM PDT August 30, 2019