Admitted to the New York bar in 1809, in January, 1810 Walworth moved to Plattsburgh, the Clinton County county seat and where his eldest brother Major John Walsworth served as clerk of the court. In 1811 Reuben Walworth was appointed a master of chancery, one of the local judges and whose particular responsibilities included overseeing and protecting widows and orphans, as well as issuing injunctions against nuisances.
