the presence of the person by subpoena." "A Criminal Proceeding" Although there has been much legal debate about the scope of the material witness statute, it has been clear since the Ninth Circuit Court of Appeals ruling in Bacon v. United States, 449 F.2d 933 (9th Cir. 1971), that the phrase "a criminal proceeding" from the material witness statute includes both trials (uncontroversially) and grand jury investigations. Thus, the ability to arrest material witnesses under the statute extends to the ability to arrest those with information material to a grand jury investigation (assuming the showing of impracticability is also made). The Supreme Court has not had a chance to rule on this statutory issue. Detentions of material witnesses after September 11 After the attacks of September 11, 2001, the United States government announced a campaign of aggressive detention, by whatever means possible, of those potentially involved in attacks on the United States. The means included using the material witness statute to detain even suspects (as opposed to witnesses). Many of those detained as material witnesses were detained as witnesses to grand jury proceedings, which only investigate and are not criminal trials. This caused controversy for several reasons. Primarily, critics believed that the government's use of the material witness statute to detain suspects was an evasion of the Fourth Amendment to the US Constitution, which provides some protections to criminal suspects that were apparently ignored in the arrests of the material witness detainees post-September 11. Secondarily, legal critics took issue with the application of the material witness statute to grand jury proceedings. Statistics on federal material witness warrant hearings showed a steady decline from 2000 to 2002, from 3603 material witness hearings in FY2000, to 3344 in FY2001 and 2961 in FY2002. During and after that period, the overwhelming majority of material witness warrant hearings took place in judicial districts bordering Mexico and involved illegal alien traffic. Attempting to amend the material witness statute In 2005, with the intent of alleviating concerns over such use of the material witness statute, Democratic Party Senator Patrick Leahy proposed A Bill to Amend the Material Witness Statute to Strengthen Procedural Safeguards, and for Other Purposes, § 1. The legislation failed to move forwards, however, after being sent to the Senate Judiciary Committee. A 2006 ruling found that material witness law could only be used when an individual is genuinely sought as a witness and