In A Remonstrance 0f Many Thousand Citizens - what a title! - (July 1646) the authors complain:
For we must deal plainly with you: you have long time acted more like the House of Peers than the House of Commons. We can scarcely approach your door with a request or motion, though by way of petition, but you hold long debates whether we break not your privileges. The king's or the Lords' pretended prerogatives never made a greater noise nor was made more dreadful than the name of privilege of the House of Commons.
They may not be sending people to prison for having the wrong opinions, or engaging in "fishing expedition" interrogations any more: but there are precious few legal brakes on what the House of Commons might be able to do if a sufficient majority thought they could get away with it, even if at the moment we only face minor nonsenses about priority in queues at Westminster or some eyebrow-raising expenses claims.