U.S. Supreme Court Justice Anthony Kennedy testifies before the House Financial Services and General Government Subcommittee on Capitol Hill March 8, 2007 in Washington, DC. Kennedy and Justice Clarence Thomas spoke about concerns with the ongoing remodeling of the court building, the reduction of paperwork due to electronic media and the disparity of pay between federal judges and lawyers working in the private sector.
Chip Somodevilla/Getty Images
U.S. Supreme Court Justice Anthony Kennedy testifies before the House Financial Services and General Government Subcommittee on Capitol Hill March 8, 2007 in Washington, DC. Kennedy and Justice Clarence Thomas spoke about concerns with the ongoing remodeling of the court building, the reduction of paperwork due to electronic media and the disparity of pay between federal judges and lawyers working in the private sector.
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FILE - In this Oct. 10, 2017, file photo, the Supreme Court in Washington is seen at sunset. The Supreme Court is ordering Washington courts to take a new look at the case of a florist who refused to provide services for the wedding of two men because of her religious objection to same-sex marriage. The justices' order Monday means the court is passing for now on the chance to decide whether business owners can refuse on religious grounds to comply with anti-discrimination laws that protect LGBT people.(AP Photo/J. Scott Applewhite, File)
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WASHINGTON - MARCH 08:  U.S. Supreme Court Justice Anthony Kennedy testifies before the House Financial Services and General Government Subcommittee on Capitol Hill March 8, 2007 in Washington, DC. Thomas and fellow Justice Clarence Thomas spoke about concerns with the ongoing remodeling of the court building, the reduction of paperwork due to electronic media and the disparity of pay between federal judges and lawyers working in the private sector.  (Photo by Chip Somodevilla/Getty Images)
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WASHINGTON - MARCH 08: U.S. Supreme Court Justice Anthony Kennedy testifies before the House Financial Services and General Government Subcommittee on Capitol Hill March 8, 2007 in Washington, DC. Thomas and fellow Justice Clarence Thomas spoke about concerns with the ongoing remodeling of the court building, the reduction of paperwork due to electronic media and the disparity of pay between federal judges and lawyers working in the private sector. (Photo by Chip Somodevilla/Getty Images)
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(CNN) —  

Justice Anthony Kennedy, a conservative who provided key votes for same sex-marriage, abortion access and affirmative action, on Wednesday announced his plans to retire from the Supreme Court, effective July 31.

Read his letter to President Donald Trump

My dear Mr. President,

This letter is a respectful and formal notification of my decision, effective July 31 of this year, to end my regular active status as an Associate Justice of the Supreme Court, while continuing to serve in a senior status, as provided in 28 U.S.C 371 (b).

For a member of the legal profession it is the highest of honors to serve on this Court. Please permit me by this letter to express my profound gratitude for having had the privilege to seek in each case how best to know, interpret, and defend the Constitution and the laws that must always conform to its mandates and promises.

Respectfully and sincerely,

Anthony Kennedy