As part of the rearguard that enabled some of the Scots to escape, Lockhart was captured and held in Hull for a year. He was released after paying a fine of £1,000; he returned to Scotland but the 1649 Act of Classes passed by the Kirk Party banned former Engagers from political or military office. This meant he played no part in the Third English Civil War, an attempt by the Kirk Party to restore Charles II to the English throne.