The Instrument of Government
The Instrument of Government was a constitutional settlement drafted by Major-General John Lambert during the autumn of 1653 and adopted by the Council of Officers when the Nominated Assembly surrendered its powers to Oliver Cromwell in December. Lambert's original intention had been that the old constitution of King, Lords and Commons should be replaced by one of King, Council and Parliament. In discussion with a few trusted advisers after the abdication of the Nominated Assembly, Cromwell amended the Instrument to avoid reference to the royal title, which was likely to be unacceptable to the Army.
England's first written constitution
Under the terms of the Instrument of Government, executive power passed to an elected Lord Protector, in consultation with a Council of State numbering between thirteen and twenty-one members. Cromwell was declared Lord Protector for life, though it was stressed that the office was not hereditary. He was required to call triennial Parliaments consisting of a single House of 400 members from England and 30 each from Scotland and Ireland, to remain in session for at least five months.
Parliamentary constituencies were re-arranged in an attempt to lessen the influence of the gentry in favour of the emerging middle class who, it was hoped, would be more inclined to support the Protectorate government. The number of MPs from towns and boroughs (where voting was traditionally influenced by the local gentry) was significantly reduced and representation of the universities was limited. To balance the representative, the number of MPs from the counties was correspondingly increased.
In a direct repudiation of Leveller ideas, the county franchise was restricted to persons with land or personal property valued at £200 or more. The borough franchise remained with aldermen, councillors and burgesses. Furthermore, Roman Catholics and known Royalists were declared ineligible to vote or seek election.
Under the Instrument, Parliament was charged with raising revenue for establishing and maintaining a standing army of 10,000 horse and dragoons and 20,000 foot for the defence of England, Scotland and Ireland.
Liberty of worship was granted to all except Roman Catholics and those guilty of "licentiousness" (i.e. the extreme sectarians).
The Instrument of Government was England's first written constitution. It was adopted by the Council of Officers on 15 December 1653 and Cromwell was installed as Lord Protector the next day. The First Protectorate Parliament duly assembled on 3 September 1654. However, the abrupt termination of Parliament in January 1655 meant that MPs never finished revising the Instrument of Government and so it was never legally endorsed. Doubts regarding its legal authority led to the resignation of the Lord Chief Justice Henry Rolle in June 1655.
The Instrument was superseded in 1657 by the Humble Petition and Advice.
S.R. Gardiner, History of the Commonwealth and Protectorate vol. iii, 1903
Ronald Hutton, The British Republic 1649-60, 2000
Instrument of Government full text www.constitution.org