The American Civil Liberties Union on Wednesday filed a lawsuit challenging a 30-year-old hacking-crimes law, saying the law inhibits research about online discrimination.

The civil rights group is challenging the Computer Fraud and Abuse Act on behalf of a group of academic researchers, computer scientists, and journalists. The CFAA limits online research because of its “overbroad criminal prohibitions,” the ACLU said.

The group of plaintiffs in the lawsuit want to investigate online discrimination in areas like housing and employment, “but they often can’t,” the ACLU said in a blog post. Courts have interpreted a provision of the CFAA prohibiting people from exceeding authorized access to a computer to include violations of website terms of service, the ACLU said.

Some terms of service prohibit providing false information, creating multiple accounts, or scraping the content of websites.

“The problem is that those are the very methods that are necessary to test for discrimination on the internet, and the academics and journalists who want to use those methods for socially valuable research should not have to risk prosecution for using them,” ACLU staff attorneys Esha Bhandari and Rachel Goodman wrote.

The CFAA violates First Amendment free-speech rights “because it limits everyone, including academics and journalists, from gathering the publicly available information necessary to understand and speak about online discrimination,” they added.

Some researchers want to test whether websites are more likely to show higher interest rate loan ads to racial minorities or show higher paying jobs to men searching employment listings, the ACLU said.

The plaintiffs in the lawsuit include two professors researching online discrimination, two more computer science professors, and First Look Media, which publishes The Intercept.

The U.S. Department of Justice didn’t immediately respond to a request for comments on the lawsuit.