[7][8] He defeated Democratic lawyer Matt Flynn in November 1978 with 61% [9] and was reelected 20 more times with no substantive opposition, sometimes running unopposed in what has long been the most Republican district in Wisconsin.

Although the primary author was Assistant Attorney General of the United States Viet Dinh,[15] Sensenbrenner has been recognized as "one of the architects of the Patriot Act".

In 2006, the NRA successfully lobbied Sensenbrenner to add a provision to the Patriot Act re-authorization that requires Senate confirmation of ATF director nominees.

[17] In 2005, Sensenbrenner authored the Real ID Act, which requires scrutiny of citizenship before issuing drivers' licenses to make it more difficult for terrorists and criminals to alter their identities by counterfeiting documents.

Sensenbrenner defended his actions by stating that the Democrats and witnesses had violated House rules in discussing issues unrelated to the subject of the meeting.

[20] In June 2013, Sensenbrenner objected to the FBI and NSA's use of the PATRIOT Act to routinely collect phone metadata from millions of Americans without any suspicion of wrongdoing.

[21] He released a statement saying: "While I believe the Patriot Act appropriately balanced national security concerns and civil rights, I have always worried about potential abuses.

"Never, he said, did he intend to allow the wholesale vacuuming up of domestic phone records, nor did his legislation envision that data dragnets would go beyond specific targets of terrorism investigations."

[28] In March 2005, Sensenbrenner sided with the parents and siblings in the Terri Schiavo case, who fought unsuccessfully in federal court to block the withdrawal of her feeding tube.

4437, a bill passed by the House in 2005 that would provide additional criminal penalties for aiding and abetting illegal immigration to the United States.

[30] Sensenbrenner, in spite of unanimous Congressional support,[31] attempted to delay a bill[32] in December 2010 that would have been benefited Hotaru Ferschke, the Japanese-born widow of a United States Marine killed in combat.

He helped lead the effort to pass the Intellectual Property Protection Act of 2006, which was supported by large copyright holders and opposed by fair use activists.

[36] In 2017, Sensenbrenner joined fellow Congressional Republicans in overturning policies put in place by the Obama administration that required telecommunication carriers like Verizon, AT&T, and Comcast to allow customers to opt in or out from those companies' sharing their confidential information.

"[37] In 2006, Sensenbrenner expressed outrage at the FBI raid of the congressional office of Democratic Representative William J. Jefferson, asserting constitutional concerns over separation of powers.

[39] In fall 2006, the Animal Fighting Prohibition Enforcement Act unanimously passed the Senate, but Sensenbrenner used his position to block final House consideration of the legislation, even though the bill had 324 co-sponsors.

[40] Sensenbrenner was the only Republican to join House Speaker Nancy Pelosi's Congressional delegation to meet the Dalai Lama in Dharamsala, India during the March 2008 protests against China by Tibetans.

[45] Sensenbrenner believes in criminal prosecution of broadcasters and cable operators who violate decency standards, in contrast to the FCC regulatory methods.

[46] In July 2012, Sensenbrenner advocated amending the Espionage Act of 1917 to enable the prosecution of journalists involved in publishing leaks of state secrets.

[52][53] Also in 2006, the NRA lobbied Sensenbrenner to add a provision to the Patriot Act re-authorization that requires Senate confirmation of ATF director nominees.

[56] He is currently a visiting fellow at Johns Hopkins School of Advanced International Studies, his research focusing on Eurozone financial markets, and has blogged for the Huffington Post on Italian politics and the Vatican.