Warburton was one of the commissioners appointed on 1 February 1641 for the levy in Cheshire of the first two subsidies granted by the Long Parliament, and on 6 November 1645 was added to the committee of accounts. Parliament also appointed him on 22 February 1647 justice of the court of session of Cheshire and of the great sessions of Montgomeryshire, Denbighshire, and Flintshire, and advanced him on 12 June 1649 to a puisne judgeship in the Court of Common Pleas, having first (9 June) caused him to be invested with the coif.