Captain Joseph Sheffield was a landowner, farmer, and lawyer and was prominent in the political affairs of the Rhode Island Colony. He was a freeman in Portsmouth 14:6:1683 and of the colony on 6:6:1684. He served on various juries, was constable for the town, was a moderator for town meetings, and deputy to the General Assembly. He served on a committee of five to settle boundaries of the towns of Kingston, Westerly and Greenwich. He and six others were elected to transcribe the laws of the Colony. He was appointed Colonial Agent to England, was one of a committee to address the Crown regarding the Rhode Island militia. He was one of the Rhode Island Commissioners settling boundary disputes with Connecticut, and served with two others on a committee to draft laws of the procedure in the Court of Rhode Island of Common Pleas. From 1704-1706 he was Attorney General of Rhode Island, and in 1705 he was on a commission to transcribe and print the Colony's laws. He was active in the popular party of the Colony which opposed the encroachments of the Crown on the Colony.
Joseph Sheffield's Portsmouth lands adjoined those of his father, Ichabod, and in addition he had a large tract of land in the Narragansett Country in what are now the towns of North and South Kingston.
(from G. Andrew Moriarty, One Branch of the Rhode Island Sheffields in Colonial Rhode Island Vol. 2))