A group of Internet and intellectual property law professors have penned a letter to congressional lawmakers in opposition to the Protect IP Act, which would give the government sweeping new powers to take websites offline, censor search engines and sue Internet publishers accused of infringing activities.

In the letter, they warn that the act would "undermine" U.S. leadership on freedom of speech issues, cautioning that provisions within the legislation are more closely aligned with "repressive regimes" than the traditional American stance on Internet freedom.

They also predict that the Protect IP Act would threaten the security of the Internet at large, as it would give U.S. officials the authority to literally break the Internet's domain name system (DNS), which links servers to web domains for easy access to pages around the world.