A federal rule that requires tobacco companies to display pictures of diseased lungs or other graphic images on cigarette packs is unconstitutional, a judge in Washington ruled Wednesday.

Regulations by the U.S. Food and Drug Administration would have required tobacco companies to display the images on the top half of cigarette packs, front and back. It was scheduled to take effect in September.

U.S. District Judge Richard Leon said the Obama administration failed "to convey any factual information supported by evidence about the actual health consequences of smoking through its use of these graphic images." The rule, he said, violates companies' First Amendment protections against government-compelled speech.

Several tobacco companies, including R.J. Reynolds, Lorillard and Liggett Group, filed a lawsuit against the FDA in August, challenging the rule, which stems from the 2009 Family Smoking Prevention and Tobacco Control Act.

The government can compel companies to disclose factual, uncontroversial information, to protect consumers from deception or confusion. But the compelled speech can't be overly burdensome.