Civil War to the Act of Union and beyond
The gradual collapse of the Charles I's government prior to the Civil War enabled the House of Lords to assume a greater judicial role, and although the House was abolished in 1649 it was restored to its former position, complete with a Committee for Petitions, in 1660.
Following a long-running dispute with the House of Commons, in which the Lords was pressured to consider a petition from the East India Company which did not originate in a lower court, in practice the Lords limited its jurisdiction to cases on appeal from lower courts.
In 1675 the Commons sought to limit the Lords' right to hear petitions to decisions of the common law courts and to exclude challenges to decisions from the court of equity. The Lords' right to exercise this latter jurisdiction, however, remained unchanged.
Following the Act of Union with Scotland in 1707 the jurisdiction of the House of Lords was extended to appeals from the Scottish courts. There were soon a large number of appeals from the Edinburgh-based Court of Session and in 1713 the Lords accepted an appeal from the High Court of Justiciary, the highest criminal court in Scotland.
But when in 1781 the Earl of Mansfield pointed out there had been no appeal from the Court of Justiciary prior to the Act of Union, the Lords agreed to consider no further criminal appeals from Scotland.