A bill giving the government the power to shut down Web sites that host materials that infringe copyright is making its way quietly through the lame-duck session of Congress, raising the ire of free-speech groups and prompting a group of academics to lobby against the effort.

The Combating Online Infringement and Counterfeits Act (COICA) was introduced in Congress this fall by Sen. Patrick Leahy (D-VT). It would grant the federal government the power to block access to any Web domain that is found to host copyrighted material without permission.