Twitter is enlisting its users to help combat misinformation on its service by flagging and notating misleading and false tweets.

The pilot program unveiled Monday, called Birdwatch, allows a preselected group of users – for now, only in the U.S. – who sign up through Twitter. Those who want to sign up must have a U.S.-based phone carrier, verified email and phone number, and no recent Twitter rule violations.

Twitter said it wants both experts and non-experts to write Birdwatch notes. It cited Wikipedia as a site that thrives with non-expert contributions.

“In concept testing, we’ve seen non-experts write concise, helpful and easy-to-understand notes, often citing valuable expert sources,” the company wrote in a blog post.