Since 9/11, the F.B.I. has turned more frequently to an administrative subpoena, known as a national security letter, to demand such records.

The data is obtained using broad administrative subpoenas, not court warrants.

Advocate the prohibition of searches and seizures not conducted with judicial oversight, including administrative subpoenas.

The original Patriot Act made major changes in money-laundering laws that provided for the use of administrative subpoenas.

The Treasury Department has used broad administrative subpoenas to get access to transactions from Swift, often millions of records at a time.

The other main sticking point is an administrative subpoena, called a national security letter, that gives the federal government the power to demand records without a judge's approval.

The Justice Department used administrative subpoenas more than 3,900 times in a variety of cases in 2001, the last year for which data was available.

The bill's defenders note that administrative subpoenas are already allowed in other kinds of investigations.

It mirrors a proposal that President Bush outlined in a speech two months ago to expand the use of administrative subpoenas in terrorism cases.

One of Mr. Burnside's main complaints was that the Government had been reluctant to use administrative subpoenas.