A Republican Constitution?

One way of reading yesterday's success of the British parliament is to claim, as Adam Tomkins does, that the British Constitution is fundamentally Republican. Three elements characterise Tomkins' Republicanism: Anti-monarchism and Popular Sovereignty; freedom as non-domination (following P. Pettit account of this concept); and the institutional design of accountability.

Probably, the last element, the institutional design of accountability, is the most important for Tomkins account. In his book, he spends a lot of time explaining why the notion of political accountability of the executive vis-a-vis the parliament is so central in British Republicanism.

Indeed, yesterday success of the parliament, and defeat of the executive, could be explained in Tomkins' terms. From that perspective, the Parliament would be the best institution to protect the freedom of the polity from the domination of its very government.

Any other views on this?