U.S. Senator Dianne Feinstein announced last month that she will not seek a sixth term in 2024, after having represented the state of California for more than three decades. Her retirement will mark the end of a political career that has been historic on multiple fronts.

At 89, Feinstein is the oldest sitting member of Congress. She was the first woman elected to the Senate from California, the first woman to chair the Senate Rules Committee and Senate Intelligence Committee, and is the longest-serving woman in Senate history.

In honor of Women’s History Month, below are some of the most significant issues Feinstein has worked on since her election to the Senate in 1992.

Assault Weapons Ban

dianne feinstein speaking into a microphone at a podium, with assault weapons mounted on a display behind her
U.S. Senator Dianne Feinstein speaks next to a display of assault weapons during a news conference in January 2013 on Capitol Hill.
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Feinstein is arguably best known for her efforts to enact stricter gun control laws, particularly her spearheading of the 1994 Federal Assault Weapons Ban during her first term. The bill, signed into law by President Bill Clinton, prohibited the manufacture of certain semi-automatic firearms and large-capacity ammunition magazines for civilian use.

Although the final bill was a diluted version of Feinstein’s original legislation, it outlawed weapons like Kalashnikov- and AR-15–style rifles typically used in mass shootings. The ban expired in 2004, and efforts by Feinstein and other Democrats to renew it have not succeeded.

The National Rifle Association and other critics have called the legislation ineffective, but Feinstein has pushed back against such claims, citing reports that gun massacres decreased by 37 percent while the ban was in place and rose by 183 percent after it expired.

Torture Investigation and Report

Feinstein led the Senate’s six-year review of the CIA’s detention and interrogation program—and particularly its use of torture—following the September 11 attacks. The result was a sweeping indictment of the agency and its treatment of terrorism suspects.

The full 6,700-page torture report, which drew upon millions of CIA documents, remains classified, but Feinstein helped push for the public release of a 525-page executive summary, which was issued in 2014 over the objections of the agency and President Barack Obama.

Feinstein has called this the most important work of her career, as well as the most important oversight activity ever conducted by the Senate Intelligence Committee.

Same-Sex Marriage Protections

a black and white photo of dianne feinstein sitting and listening to something, with her hand on her mouth
U.S. Senator Dianne Feinstein in a meeting in July 1994
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Feinstein was one of just 14 senators to vote against the Defense of Marriage Act (DOMA) in 1996, which defined marriage as the union of one man and one woman, effectively banning same-sex marriage in the United States.

She joined an amicus brief urging the U.S. Supreme Court to legalize same-sex marriage, which it ultimately did with the landmark case United States v. Windsor in 2013. Feinstein also introduced the Senate version of the Respect for Marriage Act, which repealed DOMA and required all states and territories to recognize the validity of same-sex marriage. The act was signed into law by President Joe Biden in December 2022.

Desert Protections

The protection and preservation of California deserts had been a priority for Feinstein from her first term when she sponsored the Desert Protection Act of 1994, which established the Death Valley National Park, Joshua Tree National Park, and Mojave National Preserve. The law protected more than 7.6 million acres of California desert wilderness. In 2019, Feinstein pushed for the passage of additional public land bills to update and expand those protections.

Amber Alert System Expansion

patrick leahy hugging a laughing dianne feinstein as both hold binders, with orrin hatch standing next to them and smiling
Senator Patrick Leahy embraces Senator Dianne Feinstein before an Amber Alert press conference at the U.S. Capitol in January 2003.
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Along with Senator Kay Bailey Hutchison of Texas, Feinstein supported bipartisan legislation in 2002 to expand the reach of child abduction alert systems across state lines and to establish a dedicated Amber Alert coordinator in the Justice Department to help organize those efforts. The original bill stalled in Congress, but President George W. Bush signed an executive order establishing many of its provisions, and the legislation was finally passed in 2003.

Lake Tahoe Conservation

Feinstein helped pass the Lake Tahoe Restoration Act in 2000, creating a $1.9 billion public-private partnership to conserve and restore the environment of the Lake Tahoe Basin in California and Nevada. In 2016, Feinstein co-sponsored bipartisan legislation to extend the partnership another 10 years, adding another $415 million to the restoration funds.

Human Trafficking Reduction

senator charles grassley and dianne feinstein, both wearing glasses, seated and listening to something off camera
Senators Chuck Grassley and Dianne Feinstein in 2018
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Together with Iowa Senator Chuck Grassley, Feinstein introduced bipartisan legislation last year to reauthorize and update the Trafficking Victims Protection Act, which seeks to prevent human and sex trafficking, provide services to victims, and increase federal coordination for the government’s response to the issue. Feinstein also authored a bill to protect young athletes from sexual abuse. Both bills were passed in the Senate.

Cybersecurity Legislation

Feinstein worked with North Carolina Senator Richard Burr to secure passage of the Cybersecurity Information Sharing Act, the nation’s first major cybersecurity bill. It called for information sharing between private companies and the government and included privacy safeguards and liability protections for citizens. The bill was signed into law by President Obama in 2015.

Consumer Adovacy

Feinstein has championed several bills protecting consumers during her time in the Senate, including legislation that banned phthalates in toys and products designed for children. She worked with Alabama Senator Jeff Sessions on legislation to stop rogue Internet pharmacies and called on the U.S. Department of Agriculture to finalize stronger pathogen standards for poultry products.

Fuel Efficiency Improvements

Along with Senator Olympia Snowe of Maine, Feinstein co-authored the 2007 Ten-in-Ten Fuel Economy Act, which required automakers to increase fleet-wide fuel economy. That legislation helped inform the fuel efficiency standards for medium- and heavy-duty vehicles that Obama presented in 2016.

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Colin McEvoy
Senior News Editor, Biography.com

Colin McEvoy joined the Biography.com staff in 2023, and before that had spent 16 years as a journalist, writer, and communications professional. He is the author of two true crime books: Love Me or Else and Fatal Jealousy. He is also an avid film buff, reader, and lover of great stories.