Several legal experts said that by redefining the meaning of “electronic surveillance,” the new law narrows the types of communications covered in the Foreign Intelligence Surveillance Act, known as FISA, by indirectly giving the government the power to use intelligence collection methods far beyond wiretapping that previously required court approval if conducted inside the United States.

These new powers include the collection of business records, physical searches and so-called “trap and trace” operations, analyzing specific calling patterns.

Though many Democratic leaders opposed the final version of the legislation, they did not work forcefully to block its passage, largely out of fear that they would be criticized by President Bush and Republican leaders during the August recess as being soft on terrorism.