Restrictions on the Lords' right to amend bills

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37.15The Commons' resolution of 1678, cited on para 37.6, conceals, in its final clause, a very important distinction between two kinds of amendment by the Lords which, as breaches of privilege, are of very unequal significance in the eyes of the Commons. One of them is often tolerated, the other never. This distinction depends upon a distinction of kind in the bills amended. There is a certain kind of bill which descends from the earliest days of the Commons' history, and which is felt by them to embody privilege in its most essential form. This is the ‘Bill of Aids and Supplies’.1 The four types of such bills are described in para 36.43. The most common types are Finance Bills for taxation and Supply and Appropriation Bills for expenditure. Any amendment by the Lords of such a bill, whether or not the amendment in itself involves interference with a charge, is regarded by the Commons as an intolerable breach of privilege.2 In the case of any other bill, to constitute a breach of privilege, an amendment must in itself involve some interference in a charge. The Commons feel themselves at liberty to accept such breaches of privilege when they choose, with no more than a special record of the fact that they have waived their privilege. The practice is, therefore, treated here under the separate headings:

  1. Lords amendments to Bills of Aids and Supplies.
  2. Lords amendments to other bills.


  1. 1. This historical term is no longer in common use, but still appears in SO No 80 (House of Commons) and (in a slightly different form) in SO No 51 (House of Lords).
  2. 2. 3 Hatsell 153–54.