Facebook weighed in this week on a case in Virginia examining whether “liking” something on the social network constitutes free speech.

In a friend of the court filing with the Eastern District of Virginia, Facebook said that expressing a preference for something by hitting the Like button should absolutely be protected under the First Amendment. It not only clearly expresses a preference for something, it is also often intended to spark conversation and discussion, the company argued.

In this particular case, the court is deliberating whether it was right for sherriff B.J. Roberts of Hampton, Va., to dismiss six people who supported his opponent in a 2009 election — including deputy sheriff Daniel Ray Carter, Jr., who “liked” the Facebook campaign of his boss’ challenger. Roberts eventually won the election.

In May, U.S. District Court Judge Raymond A. Jackson ruled that Carter’s statement was not protected under the constitution because it was not an actual statement of support, but rather “insufficient speech to merit constitutional protection.” Put another way, it had no words.

But, Facebook argued in its filing this week, that’s simply not how the Like button is used.

“Liking a Facebook Page (or other Web site) is core speech,” the company wrote in the brief. Deciding to like the other campaign, the network argues, is “the 21st-century equivalent of a front-yard campaign sign.”

Facebook has at least one major ally when it comes to this position: the American Civil Liberties Union, which filed a similar brief with the court on Monday, comparing hitting the Like button to other representative forms of speech such as wearing a pin or placing a bumper sticker on a car.

In its brief, the organization wrote, “Whether someone presses a ‘Like’ button to express those thoughts or presses the buttons on a keyboard to write out those words, the end result is the same: one is telling the world about one’s personal beliefs, interests, and opinions. That is exactly what the First Amendment protects, however that information is conveyed.”

(Post Co. Chairman and chief executive Donald E. Graham is a member of Facebook’s board of directors.)

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