John Choon Yoo (Korean: 유준; born July 10, 1967)[2] is a South Korean-born American legal scholar and former government official who serves as the Emanuel S. Heller Professor of Law at the University of California, Berkeley.

Yoo became known for his legal opinions concerning executive power, warrantless wiretapping, and the Geneva Conventions while serving in the George W. Bush administration, during which he was the author of the controversial "Torture Memos" in the War on Terror.

[23] Yoo has been principally associated with his work from 2001 to 2003 in the Department of Justice's Office of Legal Counsel (OLC) under Attorney General John Ashcroft during the George W. Bush Administration.

[25] In what was originally known as the Bybee memo, Yoo asserted that executive authority during wartime allows waterboarding and other forms of torture, which were euphemistically referred to as "enhanced interrogation techniques"[26] were issued to the CIA.

Secretary of State Colin Powell strongly opposed what he saw as an invalidation of the Geneva Conventions,[28] while U.S. Navy general counsel Alberto Mora campaigned internally against what he saw as the "catastrophically poor legal reasoning" and dangerous extremism of Yoo's opinions.

[29] In December 2003, Yoo's memo on permissible interrogation techniques was repudiated as legally unsound by the OLC, then under the direction of Jack Goldsmith.

[30] On March 14, 2003, Yoo wrote a legal opinion memo in response to the General Counsel of the Department of Defense, in which he concluded that torture not allowed by federal law could be used by interrogators in overseas areas.

[32][33] Yoo's contribution to these memos has remained a source of controversy following his departure from the Justice Department;[34] he was called to testify before the House Judiciary Committee in 2008 in defense of his role.

[35] The Justice Department's Office of Professional Responsibility (OPR) began investigating Yoo's work in 2004 and in July 2009 completed a report that was sharply critical of his legal justification for waterboarding and other interrogation techniques.

[36][37][38][39] The OPR report cites testimony Yoo gave to Justice Department investigators in which he claims that the "president's war-making authority was so broad that he had the constitutional power to order a village to be 'massacred.

The co-plaintiffs to the war crimes prosecution included Adolfo Pérez Esquivel, Martín Almada, Theo van Boven, Sister Dianna Ortiz, and Veterans for Peace.

That, after all, is the teaching of United States v. Altstötter, the Nuremberg case brought against German Justice Department lawyers whose memoranda crafted the basis for implementation of the infamous 'Night and Fog Decree'.

[24][6][52][28] Yoo authored the October 23, 2001 memo asserting that the President had sufficient power to allow the NSA to monitor the communications of US citizens on US soil without a warrant (known as the warrantless wiretap program) because the Fourth Amendment does not apply.

"Because the United States is at war with Al Qaeda, the President possesses the constitutional authority as Commander-in-Chief to engage in warrantless surveillance of enemy activity.

"[58] In a Wall Street Journal opinion piece in July 2009, Yoo wrote it was "absurd to think that a law like FISA should restrict live military operations against potential attacks on the United States.

[64][65][66][67] His positions on the unitary executive are controversial as well because they are seen as an excuse to advance a conservative deregulatory agenda; the unitary executive theory says that every president is able to roll back any regulation passed by previous presidents, and it came to prominence in the Reagan administration as a "legal strategy that could enable the administration to gain control of the independent regulatory agencies that were seen as impeding the...agenda of deregulating business.

"[68] Following his tenure as an appointee of the George W. Bush administration, Yoo criticized certain views on the separation of powers doctrine as allegedly being historically inaccurate and problematic for the global war on terrorism.

[70] In an opinion piece in the WSJ, he argued that the Clinton administration misused the privilege to protect the personal, rather than official, activities of the President, such as in the Monica Lewinsky affair.

[73] In 2019, on Fox News, Yoo made the comment "Some might call that espionage"[74] when discussing Lt. Col. Alexander Vindman, the top Ukraine expert on the National Security Council.

Vindman was set to testify in front of Congress the next day about Trump requesting that the Ukrainian president start an investigation into his political rival Joe Biden.

[82][83] At a July 2024 National Conservatism Conference meeting, former Donald Trump attorney John Eastman, who also clerked for Justice Clarence Thomas, had been disbarred and was facing prosecution for his alleged role in the Pence card conspiracy to overturn the 2020 presidential election results, remarked, "We've got to start impeaching these judges for acting in such an unbelievably partisan way from the bench."

[86][87][88] Soon after his appointment in October 2003 as chief of the Office of Legal Counsel, DOJ, Jack Goldsmith withdrew Yoo's torture memoranda.

[94] Yoo contended that the OPR had shown "rank bias and sheer incompetence", intended to "smear my reputation", and that Margolis "completely rejected its recommendations".

[95] Although stopping short of referral to the bar, Margolis had also written: [Yoo's and Bybee's] memoranda represent an unfortunate chapter in the history of the Office of Legal Counsel.

In foreign relations, Yoo has argued that the original understanding of the Constitution gives the President the authority to use armed force abroad without congressional authorization, subject to Congress's power of the purse; that treaties do not generally have domestic legal force without implementing legislation; and that courts are functionally ill-suited to intervene in foreign policy disputes between the President and Congress.

[citation needed] In international law, Yoo has written that the rules governing the use of force must be understood to allow nations to engage in armed intervention to end humanitarian disasters, rebuild failed states, and stop terrorism and the proliferation of weapons of mass destruction.

[105] Yoo's book, The Powers of War and Peace: The Constitution and Foreign Affairs after 9/11, was praised in an Op-Ed in The Washington Times, written by Nicholas J. Xenakis, an assistant editor at The National Interest.