Administrative law judge

An administrative law judge (ALJ) in the United States is a judge and trier of fact who both presides over trials and adjudicates the claims or disputes (in other words, ALJ-controlled proceedings are bench trials) involving administrative law.

ALJs can administer oaths, take testimony, rule on questions of evidence, and make factual and legal determinations. And depending upon the agency's jurisdiction, proceedings may have complex multi-party adjudication, as is the case with the Federal Energy Regulatory Commission, or simplified and less formal procedures, as is the case with the Social Security Administration.

The Administrative Procedure Act of 1946 (APA) requires that federal ALJs be appointed based on scores achieved in a comprehensive testing procedure, including a four-hour written examination and an oral examination before a panel that includes an Office of Personnel Management representative, an American Bar Association representative, and a sitting federal ALJ. Federal ALJs are the only merit-based judicial corps in the United States.

In American administrative law, ALJs are Article I judges under the U.S. Constitution. As such, they do not exercise full judicial power, essentially, the power over life, liberty, and property. However, Article I judges and courts are not constrained to rendering opinions for only a "case or controversy" before them, and may render advisory opinions on a purely prospective basis, such as, e.g., Congressional reference cases assigned to the Court of Federal Claims. Agency ALJs do not have the power to offer such advisory opinions, as it would be in violation of the power afforded them under the Administrative Procedures Act, 5 U.S.C. §557. Unlike the agency, ALJs are not policy or rule makers.

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