Catastrophically poor national leadership lies behind British populism and Brexit. Since Tony Blair, every prime minister has been worse than the last, and Boris Johnson is worst of the lot. Add in the five parallel leaders of the opposition—William Hague, Iain Duncan Smith, Michael Howard, Ed Miliband, Jeremy Corbyn—and you get the worst national leadership team in modern British history.

What went wrong? The fateful decision was taken by both Labour and the Tories when they chose to move from parliamentary democracy to activist democracy in choosing their leaders. This shift turned out to be a fundamental constitutional change, and fundamentally bad. The critical turning points were 2001 for the Tories and 2010 for Labour, when for the first-time party activists imposed leaders who were not the choice of parliamentarians. By this convoluted and uncharted process of radical change, party leaders and prime ministers are now chosen by a tiny, unrepresentative minority of the electorate.

If MPs alone had chosen Conservative leaders since John Major, Duncan Smith, Howard and May would be political footnotes, while Johnson would be a joke on Have I Got News For You. It was a fundamental mistake of British democratic practice to depart from the principle of parliamentary supremacy.

So what is to be done? State regulation of political parties in respect of their leadership selection processes is one possible answer. Far simpler, and virtually impossible to contest on the principle of parliamentary democracy, is that the House of Commons itself should choose the prime minister.

A constitutional change, by act of parliament, requiring the House of Commons to elect the prime minister after a general election would, in effect, restore parliamentary supremacy to the choice of the head of government. It would not formally interfere with internal party selection, since it would be possible to have a leader chosen by activists who was then disowned by the party’s MPs on the formation of a government after an election victory. But once this constitutional change was in place, a leader lacking the support of MPs would be unlikely, and obviously undesirable, for parties seeking to present this person to the electorate as a potential prime minister.

This precise system is at the core of the Federal Republic of Germany’s constitution (“Basic Law”) in its provisions for the selection of the chancellor, dating back to the foundation of West Germany.

Article 63 of Germany’s Basic Law states:

(1) The Federal Chancellor shall be elected by the Bundestag without debate on the proposal of the Federal President.

(2) The person who receives the votes of a majority of the Members of the Bundestag shall be elected. The person elected shall be appointed by the Federal President.

(3) If the person proposed by the Federal President is not elected, the Bundestag may elect a Federal Chancellor within fourteen days after the ballot by the votes of more than one half of its Members.

(4) If no Federal Chancellor is elected within this period, a new election shall take place without delay, in which the person who receives the largest number of votes shall be elected. If the person elected receives the votes of a majority of the Members of the Bundestag, the Federal President must appoint him within seven days after the election. If the person elected does not receive such a majority, then within seven days the Federal President shall either appoint him or dissolve the Bundestag.

These provisions are supplemented by the Rules of Procedure of the Bundestag, which require these ballots to be conducted in secret.

It is these provisions which have led to the selection of Germany’s eight chancellors since 1949, a remarkable group which includes Adenauer, Brandt, Schmidt, Kohl, Schröder, and Merkel. In the same period, Britain has had 15 prime ministers, four of them in the last decade alone.

Other parliamentary democracies also have their head of government elected by parliament. Spain, Sweden, Switzerland, Estonia, and South Africa all do this. However, there is no need to go abroad to observe secret parliamentary ballots for positions of leadership. The Speaker of the House of Commons is now chosen by secret ballot of MPs.

Electing the prime minister by parliament is an idea whose time has come, and it should be done as soon as possible.Britain’s disastrous experience of activist supremacy requires us to think anew. It is imperative to discern the basis of legitimate authority for supreme decisions of state.

Reverting to the wider issue of British populism and its constitutional remedies, having transferred the selection of party leaders to activists, parliament then, equally foolishly, handed the determination of the most crucial policy in a generation—Brexit—to a referendum without any plan.

On both counts, we should not have dismantled representative democracy so lightly.