MADISON, Wis. (AP) -

A federal judge has blocked enforcement of parts of the policy that determines who can legally gather in the Wisconsin state Capitol.

Gov. Scott Walker's administration adopted the policy in the wake of the massive demonstrations in 2011 that grew to as large as 100,000 people.

The American Civil Liberties Union in February filed a federal lawsuit on behalf of a person who regularly gathers in the Capitol over the noon hour to sing protest songs.

U.S. District Judge William Conley on Monday issued a preliminary injunction barring the Walker administration from distinguishing the type of gathering for purposes of issuing a permit. Conley also barred enforcing the permit requirement for gatherings expected to draw 20 or fewer people.

A Walker administration spokeswoman had no immediate comment.