Parliament. And this is what happened.

No sooner was the House constituted, with about 320 members present
out of the total 460, than it proposed for its first business what
was called "The Matter of the Government"; by which was meant a
review of that document of forty-two Articles, called the
_Government of the Commonwealth_, which was the constitutional
basis of the Protectorate. On Thursday, Sept. 7, accordingly, they
addressed themselves to the vital question of the whole document as
propounded in the first of the Articles. "Whether the House shall
approve that the Government shall be in one Single Person and a
Parliament": such was the debate that day in Grand Committee, after a
division on the previous question whether they should go into
Committee. On this previous question 136 had voted _No_, with
Sir Charles Wolseley and Mr. Strickland (two of the Council of State)
for their tellers, but 141 had voted _Yea_, with Bradshaw and
Colonel Birch for their tellers. In other words, it had been carried
by a majority of five that it fell within the province of the House
to determine whether the Single-Person element in the Government of
the Commonwealth, already introduced somehow as a matter of fact,
should be continued. On this subject the House debated through the
rest of that sitting, and the whole of the next, and the next, and
the next,--i.e. till Monday, Sept 11. Bradshaw, Hasilrig, and Scott
took the lead for the Republicans, not that they hoped to unseat
Cromwell, but that they wanted to assert the paramount authority of
Parliament, and convert the existing Protectorship into a derivative
from the House then sitting. Lawrence, Wolseley, Strickland, and
others of the Council of State, describable as the ministerial
members, maintained the existing constitution of the Protectorate,
and pointed out the dangers that would arise from plucking up a good