Dean of the House

The Dean of the House is not an office created by the Constitution, a statute, or the House rules, but an honorific based on seniority, which has shaped House customs since the First Congress. The title goes to the member with the longest unbroken service, regardless of party, and passes to the next most senior member when the Dean leaves. The longest-serving Dean, and the longest-serving member of Congress in history, represented Michigan for more than 59 years, from 1955 to 2015.

The Dean's main formal duty comes by custom on the opening day of each Congress, after the House elects a Speaker: the Dean administers the oath of office to the Speaker-elect, who then swears in the other members as a group. The Dean is often asked to preside at ceremonial occasions, speaks for the institution at commemorations and member funerals, and may serve as an informal adviser to newer members. State delegations also name their own deans, usually their most senior member, to coordinate on issues affecting the state.

The Senate has no equivalent title, though its president pro tempore is by tradition the longest-serving senator of the majority party. Because seniority once determined committee chairmanships, long service brought real power, but since the 1970s both parties have chosen chairs by vote and some have imposed term limits on chairs, weakening the link between seniority and influence. Supporters of seniority say it rewards experience and institutional knowledge, while critics say it favors safe seats and slows the rise of new members.