THERE are many reasons why the United Kingdom is less well-governed than it ought to be.

We can blame the decline in public ethics and the ­collapse of the “good chaps theory”. Notions of public ­service and public duty, which once supplied the ­deficiencies of our unreformed ­institutions, have been ­abandoned.

We are no longer ­surprised by the sheer brazenness of ­wrongdoing and ­corruption, nor by the impunity which shields those who belong to the charmed inner circle from any accountability for their actions.

We can also blame the lack of a proper ­constitution. They get away with it, in part, because there are no higher rules to constrain them. The doctrine of parliamentary ­sovereignty leaves nothing safe or settled. No institution has any greater solidity than that which the ­government of the day, with a well-whipped parliamentary majority, chooses to ­allow it.

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In the absence of a constitution, there are no ­established foundational principles to guide and ­constrain the exercise of power. Those ­institutions which are supposed to ensure good governance – from the civil service to the BBC – can therefore be manipulated, captured and ­undermined.

Perhaps we ought to blame Parliament ­itself. For a legally sovereign body, Parliament is ­politically weak. Parliament has repeatedly failed to hold the Government to account or exercised an effective check and balance against hurried, ill-considered, government policy.

This is a strange paradox. Parliament is ­all-powerful, yet often powerless. It can decide all things, but rarely does more than ratify ­decisions made elsewhere. It is sovereign but side-lined.

We saw evidence of the side-lining of ­Parliament last week. The Prime Minister ­announced his new watch-the-planet-burn anti-environment policy not by means of a ­ministerial statement to the House of ­Commons. This is against the Ministerial Code. But the Prime Minister is the one who enforces the ­Ministerial Code, so little can be done.

What is really at stake here is not just the need for parliamentary accountability, but the ­separation between the Prime Minister’s role as a public official – a Minister of the Crown – and his role as a party leader. Statements of ­government policy should be made in the House. Keep your politicking to the campaign stump.

The Speaker will complain against it, as he is right to do, but ultimately he has no power to enforce what is merely a politically agreed ­convention of respect for the House.

The weakness of Parliament is also, however, self-inflicted. If we want an effective House, able to scrutinise policy and legislation, to hold the Government to account, and to shape public debate, then we need MPs who have the time, inclination, and skills, to take that job seriously.

Being an MP is a flexible, multi-faceted role. It is very much up to individual MPs to make the most of it. There is scope for MPs, if they want, to focus on policy work – especially if they ­specialise in one or two discrete policy ­areas. They can then use their public platform to ­lobby, influence, and shape the debate.

Sadly, however, most MPs have been lured into the trap of thinking that their primary job is to act as brokers and trouble-shooters for their constituents.

This is such a waste. Every hour an MP spends dealing with bins and potholes is an hour that they are not spending reading bills, ­conducting committee work, or appraising themselves of the issues in the areas of policy for which they are responsible. Every ­constituency letter ­answered is another chip away at the ­institutional strength of Parliament.

We would have better politics if we freed MPs from the dull chore of constituency casework, allowing them to focus more on legislative and policy work.

That shift would take three major changes. First, we would need a new electoral system. First-past-the-post encourages a narrow, local, focus. List-based proportional representation systems – like that formerly used for elections to the European Parliament – free parliamentarians from constituency burdens and help them to concentrate on broader, more important, policy and legislative issues.

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Second, we need stronger local government. In well-run countries, people do not write to their MPs about bins and potholes. They write to their mayor, who has the power to fix them.

Third, we need a change in attitude amongst the parties. Too often, parties select candidates based on their record in local campaigning and on their willingness to act as constituency caretakers. Actual qualifications for the job of being a legislator are considered last, if at all. Policy expertise is almost a hindrance.

It is hard to avoid the conclusion that any party that selects its candidates primarily with a view to their acting as constituency janitors has already given up on changing the status quo. It has abandoned the politics of ­transformation and embraced the politics of mitigation, ­making itself comfortable in the ruins of a failed ­political system.