On November 30, 1804, for the third time in its brief history, the Senate began an impeachment trial.  The first trial in 1798 and 1799 had involved a senator previously expelled on grounds of treason.  Because that senator no longer served, the Senate dismissed the case citing lack of jurisdiction.  The second trial, in 1804, removed a federal judge for reasons of drunkenness and probable insanity.  More than the first two proceedings, however, third trial challenged the Senate to explore the meaning of impeachable crimes.

Samuel Chase had served on the Supreme Court since 1796.  A staunch Federalist and a volcanic personality, Chase showed no willingness to tone down his bitter partisan rhetoric after Jeffersonian Republicans gained control of Congress in 1801.  Representative John Randolph of Virginia orchestrated impeachment proceedings against Chase, declaring he would wipe the floor with the obnoxious justice.  The House accused Chase of  refusing to dismiss biased jurors and of excluding or limiting defense witnesses in two politically sensitive cases.  Its trial managers hoped to prove that Chase had "behaved in an arbitrary, oppressive, and unjust way by announcing his legal interpretation on the law of treason before defense counsel had been heard."  Highlighting the political nature of this case, the final article of impeachment accused the justice of continually promoting his political agenda on the bench, thereby "tending to prostitute the high judicial character with which he was invested, to the low purpose of an electioneering partizan."

At the time the Senate took up the case against the Federalist justice, its members included twenty-five Jeffersonian Republicans and nine Federalists.  Chase appeared before the Senate on January 4, 1805, to declare that he was being tried for his political convictions rather than for any real crime or misdemeanor.  His defense team, which included several of the nation's most eminent attorneys, convinced several wavering senators that Chase's conduct did not warrant his removal from office.  With at least six Jeffersonian Republicans joining the nine Federalists who voted not guilty on each article, the Senate on March 1, 1805, acquitted Samuel Chase on all counts.  A majority voted guilty on three of the eight articles, but on each article the vote fell far short of the two-thirds required for conviction.  The Senate thereby effectively insulated the judiciary from further congressional attacks based on disapproval of judges’ opinions. Chase resumed his duties at the bench, where he remained until his death in 1811.