https://thenextweb.com/syndication/2020/06/18/if-i-go-to-a-protest-what-kind-of-personal-information-might-police-collect-about-me/

On the evening of May 29, New Yorkers went out by the thousands for the first big day of protests following the murder of George Floyd. If they were checking Twitter as they headed out the door, they may have seen a surprising warning issued by Terri Rosenblatt, supervising attorney of the DNA Unit at The Legal Aid Society in New York City:

Then, when a Twitter follower asked her about the vulnerability of protesters’ face masks, Rosenblatt answered yes, “a full profile could be detected from the inside of a face mask. Hold on to your PPE, people….”