The Cybersecurity and Internet Freedom Act, introduced late Thursday, would explicitly deny the president or other U.S. officials "authority to shut down the Internet." The legislation, similar in many ways to a controversial 2010 bill, comes after persistent criticism that the bill's sponsors want to give the president a .

"We want to clear the air once and for all," Senator Joe Lieberman, a Connecticut independent, said in a statement. "There is no so-called 'kill switch' in our legislation because the very notion is antithetical to our goal of providing precise and targeted authorities to the president. Furthermore, it is impossible to turn off the Internet in this country."

In 2010, the bill's sponsors -- Lieberman, Maine Republican Susan Collins and Delaware Democrat Tom Carper -- introduced a wide-ranging cybersecurity bill that would have defined emergency powers that the president could use, including shutting down parts of the Internet, when there's an "ongoing or imminent" cyberattack on the nation's critical infrastructure.

The , again allowing the president to take emergency measures to protect critical infrastructure. But the new bill adds language saying that the president, federal cybersecurity officials and other government employees do not have the authority to shut down the Internet.

The three senators, all members of the Senate Homeland Security and Governmental Affairs Committee, argued that the bill would limit broad powers the president has in the Communications Act of 1934 to take over or shut down wired and radio communications during war time. But critics said the bill, which failed to pass through Congress, would give the president broad and ambiguous authority.