Sometime after moving to Boston, Coggeshall became an enthusiastic supporter of Anne Hutchinson, who was at the center of the growing Antinomian Controversy. Also supporting her initially were the Reverend John Cotton and many of the Boston church members. Even the colony's Governor Henry Vane was a strong admirer, but he was voted out of office and John Winthrop became the governor. At that point, strong measures were taken to "stamp out heresy and drive out the heretics," in the words of one modern historian. Anne Hutchinson was tried, convicted, and banished from the colony because of her religious opinions, her prophecies of God's wrath and destruction upon the colony, and her influence in fanning the flames of controversy within the community. At her civil trial, Coggeshall spoke out in her defense and was one of only three deputies to vote for her acquittal, the other two being William Aspinwall and William Coddington. Coggeshall also supported dissident minister Reverend John Wheelwright, whose wife was the sister of Anne Hutchinson's husband. Shortly after Hutchinson's banishment, Coggeshall was expelled from the General Court and was also directed to leave Massachusetts in March 1638.