Personally I wouldn’t say refusing to give the Royal Seal of Approval to a trivial proclamation would count as the exercise of “a whole lot of power”. Most likely Parliament would just say “Well, the old dear’s a bit cranky this week, isn’t she? But no sense going all Cromwellian with a revolution and all that stuff and nonsense. We’ll just forget about this year’s PuddingFest and move on.”
The technical language is that the Royal Veto has “fallen into desuetude”, and this is only appropriate considering how the British Constitution works: A bill becomes law when it receives Royal Assent after having been passed by Lords and Commons. Since she appoints a P.M. who can command a majority in Commons, and with a few ultra-rare exceptions she is bound to act in accordance with the advice he provides her, any bill which has passed Commons is one he will advise her to assent to. The cure for a bad statute is not in the Royal Veto but at the polls, electing a Commons which will repeal it and give their confidence to a PM who will advise her to assent to the repeal.
But desuetude does not mean sbolishment. As recently as the 1950s the Earl Marshal’s Court, long in desuetude, was revived to hear the case of a theatre illegally using a coat of arms which they were not entitled to use. The present coalition government gives a good hypothetical example of when the Veto might validly be used. Suppose that the coalition agrees to pass Bill A, which the Tories strongly favor and the LibDems mildly dislike, in exchange for Bill B, a key issue for LibDems which the Tories were neutral to unfavorable about. After Bill A has passed Commons and Lords, some of the Tories vote against and defeat Bill B. The LibDems, feeling betrayed, break the coalition and agree tp go into coalition with Labour, which with a little dealing commands a majority. Cameron resigns (or is forced out on a vote of confidence); the Queen sends for Milibanks, who advises her to refuse her assent to Bill A.
A little bit6 of a stretch, yes, but it is the sort of thing which actually could happen – and there the Royal Veto becomes a tool of democracy.
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Let me note that one major portion of the Queen’s day is taken up by “doing the boxes” – reading every cabinet-level minute and major diplomatic despatch the government gets. This, along with 60 years’ experience on the job and having observed her father during his reign, gives her unparalleled experience which is at the service of the government of the day, of whichever party. Remember she started training for this job when Hoover was President, and has worked with every PM since Churchill. And she is the one experienced advisor a PM can count on whom he can be sure doesn’t want his job. She is not a genius, but she is shrewd, and knowledgeable. A PM jgnores that resource at his peril.
The only time that I heard of the threat of a govenor general refusing to sign a bill in Canada - when Trudeau threatened to unilaterally change the constitution.
The original constitution was British Parliament’s BNA act. Trudeau said that with a majority, his party could pass whatever it wanted. The standard process was that any change to the BNA act was passed and signed into law in Canada, instructing the British Parliament to update their version of thelaw. The British then passed an update to the law.
Trudeau in his usually way (allegedly “Arrogance” was his middle name, or was it “Elliot”?) decided to ignore all the clamoring and pass what he wanted. The governor General at the time Eric Schreyer, mused that he would consider not signing such a momentous change without a wide base of public support.
Fortunately, a groundswell of public opinion and a supreme court decision made the government turn to compromise before this was put to the test. (Part of the groundswell included public demands that the Queen and British parliament not agree to a change that was not widely supported).
The other famous GG action was the time the Australian upper and lower houses were deadlocked, and the governor general there called an election rather than do what the prime minister wanted.
Indeed, and I think Sir John Kerr is unfairly criticised for it. The Australian Constitution requires supply to be ratified by both Houses of Parliament. In this instances the Senate declined to grant supply. If it had been the House, the PM would have been expected to resign, and I don’t see why the Senate should have been treated any differently if the Australian Constitution sees no difference. Kerr did the right thing and upheld the Constitution impartially. It’s not his fault there was a dumb clause in it!
It’s worth mentioning to Americans that the Kings/Queens of England/the UK haven’t had actual executive power since the Glorious Revolution of 1688 and legally since the original Bill of Rights became law in 1689.
In other words, since nearly a century before the American Revolution.
In Canada, I think that the only thing the Queen routinely does is appoint the new Governor General every five years. The GovGen then exercises all of the royal powers, as delegated by the Letters Patent Constituting the Office of the Governor General, and the various provisions of the Constitution Act, 1867which refer to the GovGen.
Exceptionally, Her Majesty has been asked to do two things that none of her predecessors were asked to do: sign the Proclamation bringing the Constitution home, as others have mentioned, and appoint extra Senators to resolve a deadlock between the Commons and Senate over the proposed GST, a power granted specifically to the Queen by the Constitution Act, 1867.
This over-states it. Those were clearly milestones in the weakening of the royal powers, but the actual decline in royal executive powers took over a century. Certainly, William III and George I exercised executive power.
From what I’ve seen, a good part of many of her public appearances involve going down a reception line, shaking hands and having a brief conversation with various people. It sounds simple, but for many such people, meeting the queen may represent the highlight of the year but it’s something that she does often. So she has to appear interested in what the person is telling her while at the same time not actually being interested. That sounds really tedious.
Here’s another data point: the role of Dutch Queen Beatrix, another ceremonial Head of State.
Clark Griswold: There’s Buckingham Palace, kids. That’s where the Queen lives and works.
Audrey Griswold: Works? What does she do, Dad?
Clark Griswold: She queens… and vacuums.
I’d say you’re the one over-stating it. There were times when kings influenced political decisions, but there hasn’t been a case I know of where a king has overruled parliament.
To put it another way… cite?
For her, it was Tuesday.
Subject: Hail to the Queen!
Queen Liz: How dare you hail when I reigning?
And, for heavens sake, what’s with those hideous hats? Has nobody ever had the courage to tell her? 
Queen Anne vetoed a Bill in 1708, but on advice. Any monarchical overruling must pre-date that. I can’t think of one off-hand that didn’t end messily for the monarch.
Heh, she’s only a wee bit older than you. How would you react to someone telling you that the fashion choices you’ve made for the past 50 years are wrong?
There are still many things which HM signs herself or need her actual approval (note they are not synonymous). She still signs Judges appointments for instance (as well as QC appointments). She might now be signing military and naval commissions as was once the case although the sheer volume in the World Wars put a stop to it (King George V insisted on signing the Commissions of the first Indian officers himself).
While she has little political power (outside of exceptional circumstance) she has a lot of influence. Her father and grandfather did on occasion kibosh things they did not like or force through own ideas. As it was, we only found out about them after the Kings were long dead. Undoubtedly she has acted in a similar way and we will find out one day when she has long since passed on
The difference is, of course, that I have impeccable taste, don’t you see?? My wife may not agree, but…
This guy might have the courage. Perfect hat, perfect “I smell a turd” look on his face. ;)
Q
Does she bestow knighthood? If not, who or what does?
She also approves all passport which is why she does not carry one. I don’t know if that means she does a shift at Lunar House twice a week or not.