Charles was one of the committee of the convention that drafted the " "Declaration and Charter of Rights and form of government for the state of Maryland"" which served as Maryland's first new constitution after it was adopted on 3 November 1776. When the convention voted to expel the 23rd proprietary governor and last royal governor, Sir Robert Eden, 1st Baronet, of Maryland, he delivered the message as the chairman of the Convention. Then, in an action typical of his style, he entertained the governor and his wife as house guests at Mount Clare Mansion until they sailed for England.