The mural Kim Houghton commissioned in Shirlington. (Photo courtesy Institute for Justice.)

Arlington County is asking a federal judge to dismiss a lawsuit filed by pet groomer Wag More Dogs that claims the county's commercial sign regulations are unconstitutional. Attorneys for the county are expected to submit a motion to dismiss today, according to county spokeswoman Diana Sun.

Wag More Dogs proprietor Kim Houghton filed the lawsuit Dec. 2 after going back and forth with the county over a dog mural she painted on the wall of her Shirlington business overlooking a county dog park. County officials made her cover the mural, claiming it was an illegal sign advertising her business.

Houghton's filing sought an injunction that would allow her to uncover it, as well as a ruling that county's sign law is unconstitutional. There is a hearing on the injunction, and Arlington's motion to dismiss, scheduled for Jan. 21 in the U.S. District Court for the Eastern District of Virginia

The deadline for Arlington's filing was actually extended from Dec. 27 to Dec. 30, according to Robert Frommer, an attorney with the Institute for Justice who represents Houghton. Frommer and his team have until Jan. 11 to respond to today's dismissal motion, and the county will have three days after that to file its response.

The county's motion for dismissal was not immediately available, but we'll update this post with the documents once they are submitted.