What are the limits of a &#39;Humble Address/Motion of Return&#39; from Westminster&#39;s House of Commons?
<p>The British Attorney General is making the argument that </p>

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  <p>it cannot be right that the Commons has the power to ask for any paper produced by the government. “Where does it end?” Can the Commons use a “humble address” to get hold of cabinet minutes, or intelligence papers. It cannot be right for the “humble address” to be used like this. &mdash;<a href="https://www.theguardian.com/politics/blog/live/2018/dec/03/brexit-may-cox-legal-advice-robbins-javid-dismisses-report-key-vote-could-be-postponed-because-may-risks-huge-defeat-politics-live?page=with:block-5c056b4fe4b04b34b3e5fdf2#block-5c056b4fe4b04b34b3e5fdf2" rel="nofollow noreferrer">The Guardian</a></p>
</blockquote>

<p>Is he right? How would one assess the validity of his claim?</p>

<p>Legally, he is wrong. By convention, he is right.</p>

<p>The courts have decided that there are no constraints on the sovereignty of parliament. Whatever parliament does is legal.</p>

<p>Therefore, legally, Her Majesty (through Her Government) cannot refuse a Humble Request.</p>

<p>However, by convention, parliament does not use these frivolously or willfully - but they <em>can</em>. In fact, they fell out of use in the latter half of the nineteenth century and it is only their recent revival that is causing consternation. There is no doubt that the politicization and weaponization of these is unwise but it is not unlawful.</p>

<p>As to how the limits would be found: HMG refuses one and parliament arrests the responsible minister for contempt. And then the second civil war starts.</p>

united-kingdom constitutional-law brexit