After the hanging of James Casey and Charles Cora the Committee of Vigilance, recognizing that they had assumed the highest functions of the law, set about to purge it’s roles of certain less than desirable characters that had joined the organization. Each company was instructed to scour it own membership and report to the executive committee on May twenty-third. Another matter deemed fit for immediate attention was the willingness of members to listen to idle stories and thus they were told to make no arrests unless authorized by the executive committee.
A black list of decidedly bad characters was assembled that featured San Francisco jailer Billy Mulligan, Bill Lewis, Dan Aldrich, John Bagley, Martin Gallagher and Yankee Sullivan. Other names were reported for investigation, but it was determined that no action be taken against anyone without two-thirds approval of members present at any vote. At the same time efforts were made to arrest Edward McGowan and Peter Wrightman as accessories to James King’s murder. There was no doubt at the time that they knew Casey intended to attack King, but no evidence has ever been produced to prove this. Still, it seems both men learned they were wanted by the committee and fled.