House Office of Congressional Ethics: History, Authority, and Procedures [Updated July 21, 2021] [open pdf - 1MB]
From the Introduction: "Since the first session of Congress in 1789, the House of Representatives and the Senate have contemplated how to judge fellow Members. Investigating and judging Members of Congress continues to be an issue for Congress. In 1964, the Senate established the Select Committee on Ethics, and in 1967, the House created the Committee on Standards of Official Conduct, which was renamed the Committee on Ethics in the 112th Congress (2011-2012). These two committees formally assumed the duties of investigating allegations of wrongdoing against Members of their respective chambers. [...] In the 110th Congress (2007-2008), the House created the Office of Congressional Ethics (OCE) to review complaints, and when appropriate, refer findings of fact to the Committee on Ethics. The OCE is the first independent, outside body charged by Congress to investigate complaints against Members and refer valid complaints to the Committee on Ethics. [...] The OCE formally opened on January 23, 2009, after adopting rules for conducting investigations and a code of conduct for its board members and staff. It has jurisdiction only over current Members, officers, and employees of the House. This report focuses only on the House of Representatives and the House ethics process."
CRS Report for Congress, R40760
Congressional Research Service: https://crsreports.congress.gov/