Analysis of information sources in references of the Wikipedia article "Pomeroy, Washington" in English language version.
On May 13, 1884, the United States House of Representatives passed a bill that cured the defects in the county-seat bill. The United States Senate approved the measure, making Pomeroy the legal county seat in Garfield County once and for all. Garfield County is the only county in Washington state to have had its county seat declared by an act of the United States Congress.