Tancredo's has staunchly supported tightening immigration requirements from Islamic countries. On September 18, 2008, Tancredo introduced H.R. 6975, the Jihad Prevention Act, which would require aliens to attest that they will not advocate installing a Sharia law system in the United States as a condition for admission, and for other purposes. Aliens failing to make such an attestation would be ineligible for admission. Further, the visa of any alien advocating the installation of a Sharia law system in the United States would be subject to revocation.