The Civil Procedure Rules 1998

[F1Counterclaims, other Part 20 claims, and set-offE+W

66.4(1) In a claim by the Crown for taxes, duties or penalties, the defendant cannot make a counterclaim or other Part 20 claim or raise a defence of set-off.

(2) In any other claim by the Crown, the defendant cannot make a counterclaim or other Part 20 claim or raise a defence of set-off which is based on a claim for repayment of taxes, duties or penalties.

(3) In proceedings by or against the Crown in the name of the Attorney-General, no counterclaim or other Part 20 claim can be made or defence of set-off raised without the permission of the court.

(4) In proceedings by or against the Crown in the name of a government department, no counterclaim or other Part 20 claim can be made or defence of set-off raised without the permission of the court unless the subject-matter relates to that government department.]