Diarmuid F. O'Scannlain

Hon. Diarmuid F. O'Scannlain

Judge, United States Court of Appeals, Ninth Circuit

Judge O’Scannlain was appointed United States Circuit Judge for the Ninth Circuit by President Reagan on September 26, 1986. He received a J.D. degree in 1963 from Harvard Law School and a B.A. in 1957 from St. John’s University. He also earned the LL.M. (Judicial Process) degree at University of Virginia Law School in 1992. He was awarded the LL.D. (honoris causa) degree by the University of Notre Dame in 2002, the LL.D. (honoris causa) degree by Lewis & Clark College in 2003 and the LL.D. (honoris causa) degree by the University of Portland in 2011.

As a judge on the U.S. Court of Appeals for the Ninth Circuit, Judge O’Scannlain has participated in over 6,000 federal cases and has written hundreds of published opinions on a broad range of subjects including constitutional law, international law, securities law, administrative law, and criminal law. He hears appeals in San Francisco (court headquarters), as well as in Los Angeles (Pasadena), Portland, Seattle, Anchorage and Honolulu. The late Chief Justice Rehnquist appointed Judge O'Scannlain to the Federal Judicial Center's Advisory Committee on Appellate Judge Education. In 2009, Chief Justice Roberts appointed Judge O’Scannlain to the International Judicial Relations Committee of the U.S. Judicial Conference and subsequently appointed him Chairman in 2010.

President George W. Bush appointed Judge O’Scannlain to the Board of Trustees of the James Madison Memorial Fellowship Foundation in 2004. Pope Benedict XVI conferred the Order of Saint Gregory the Great on Judge and Mrs. O’Scannlain in 2007.

Judge O’Scannlain’s professional interests also include judicial administration and reform, and continuing legal education. Judge O’Scannlain is former Chair of the Judicial Division of the American Bar Association and has previously chaired the ABA’s Appellate Judges Conference, its Committee on Appellate Practice, and its 9th Appellate Practice Institute. He has testified before the Senate Judiciary Committee on several occasions, the House Judiciary Subcommittee on Courts and Intellectual Property, and the Commission on Structural Alternatives for the Federal Courts of Appeals on the subject of court reorganization. In addition to serving as a faculty member at numerous federal appellate practice seminars for judges and attorneys, including New York University Law School’s Institute for Judicial Administration, Judge O’Scannlain is an Adjunct Professor at Lewis & Clark Law School where he teaches a seminar on the Supreme Court. He has served as a Moot Court Judge at distinguished law schools across the United States including Harvard, Yale Stanford, Boalt Hall (Berkeley Law), Virginia, Cornell, Notre Dame, Fordham, Alabama, University of Southern California, King Hall (U.C. Davis) and Loyola Marymount University and in China at Xiamen and Renmin Universities.

Between graduation from Harvard and investiture as a federal judge, Judge O’Scannlain was primarily engaged in private law practice. Between 1969 and 1974, he was consecutively the Deputy Attorney General of Oregon, the Public Utility Commissioner of Oregon, and Director of the Oregon Department of Environmental Quality. He retired from the U.S. Army Reserve in 1978 as a Major after 23 years Reserve and National Guard service, including four years as an enlisted man.

A first generation Irish-American son of immigrant parents from Sligo and Derry, Judge O’Scannlain is married to the former Maura Nolan and has eight children: Sean, Jane, Brendan, Kevin, Megan, Christopher, Anne, and Kate, and nineteen grandchildren. His chambers are in the Pioneer Courthouse in Portland, Oregon.


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