As I understand it, Napoleon technically required the support of the Senate and Legislative Corps but do you know of any instance in the ten years of his reign where they prevented him from doing anything or even remonstrated until the 1813 incident? The Tribunate he just abolished.
May I remind you of what he wrote to Joseph 14.3.14 (From Thomson's selection of letters,italics in text, bold mine)
"The National Guard in Paris is part of the French people and I will be master everywhere in France, as long as I have a breath in my body. Your character is quite different from mine. You like flattering people, and falling in with their ideas: I like people to please me and to fall in with mine. I am master today, every bit as much as at Austerlitz. Don't let anyone flatter the National Guard. Refuse to allow Regnaud, or anyone else, to become its advocate. I suppose they do admit that there is a difference between the time of Lafayette, when the people was sovereign, and the present moment, when I am. I have decreed that twelve battalions of the mass levy are to be raised in Paris. This measure must not be held up on any pretext whatsoever I am writing to the Ministers of Home affairs and Police to the same effect. If the people once see us doing what they like, instead of what is good for them, they will obviously imagine that they are sovereign, and will have a very poor opinion of those who govern them.
Even allowing for the stress of the moment, does that sound like a man likely to relax his grip on power any time?