The law was signed March 13, and goes into effect July 1. It will require retailers to register with the state and pay a fee in order to sell "sexually explicit material."
The lawsuit names every county prosecutor in Indiana, and aims to stop the law from going into effect July 1.
The plaintiffs contend that the law could infringe on First Amendment rights, including free speech and freedom of the press.
"We're talking about a law that has very broad, very vague and — we would contend — very unconstitutional restrictions and burdens," said Ken Falk, legal director of the American Civil Liberties Union of Indiana. "To the best of my knowledge, there is no similar law in the U.S."
State Rep. Terry Goodin, D-Crothersville, wrote the law to stop companies from opening adult stores in communities with weak zoning laws. He said that the law doesn't stop a business from selling adult materials, it just requires the retailer to declare its intention to the community.
"This is all about local control, and giving those people at the local level the opportunity to decide whether they want those types of businesses in their area," he said.
If the law targets adult businesses, then it should be written to reflect that, according to Indianapolis Art Museum CEO Maxwell Anderson. The museum store sells art history books, and Anderson pointed out that nudity plays a prominent role in the history of creativity.
"We don't want to start having to examine our bookstore and think about contents of our shelves in the way that this law requires," he said.
Another plaintiff in the suit, Indianapolis general-interest bookstore Big Hat Books, sells no material defined as obscene under state law, but it does sell literature with content that might be deemed harmful to minors.
Big Hat Books earns more than half its revenue from children's literature, and that business may dissolve if the independent book store is "labeled as a purveyor of sexually explicit materials," the complaint states.
Goodin claimed that court rulings have shown there's no gray area when it comes to defining pornography.
"Individuals, corporations, companies know whether or not they're selling pornography," he said. "There's no question about that."
He also claimed that the contention that the law infringes on First Amendment rights is "absolutely ridiculous."
"I think the folks who feel this way are being deceived by the pornography industry," he said. "It's unfortunate."
The lawsuit was filed yesterday in U.S. District Court for the Southern District of Indiana.