The government's abolition of the Political and Constitutional Reform Select Committee is a mistake, say Nick Pearce and Mathew Lawerence. It is critical that MPs and all party whips speak out in favour of the committee's re-establishment, lest the executive run riot during the critical constitutional period ahead.

Profound constitutional change will be the drumbeat of this parliament. The two unions that define the country – the United Kingdom and the European Union – will be tested and reshaped. Debates over devolution and our place in Europe will be matched by parliamentary contest over issues such as the Human Rights Act, potentially far-reaching boundary changes, and the broader, never-ending struggle between the legislature and executive over the exercise of power. Added to this, formal politics and the UK's democratic structures continue to list dangerously, a 20th-century edifice failing to keep pace with the fluidity and heterogeneity of the 21st.

Given these vitally important issues for our democracy, it would seem appropriate that such measures receive full, cross-party scrutiny in parliament. Yesterday, however, we learned that the government disagrees. By refusing to re-establish the Political and Constitutional Reform Select Committee (PCRSC), they are denying parliament the opportunity to examine such issues in depth, and so provide a much-needed form of public accountability and scrutiny on how our democracy will evolve.

This is a shabby decision. The PCRSC – set up to consider political and constitutional reform and consisting of 11 members of parliament drawn from across the political parties – has consistently produced a series of informative and influential all-party reports on a wide range of critical issues: English devolution, the need for a constitutional convention, the constitutional future of Scotland, the role and powers of the prime minister, and voter disengagement, among other things. In doing so, it has practiced what it preaches, working with civil society to break all records for a select committee in terms of levels of public participation and engagement. Democratic life will be poorer by its absence.

The government has claimed that existing committees – Public Administration and Communities and Local Government, for example – can provide scrutiny over constitutional and political reform. However, these committees are already extremely busy with important scrutiny work in their own right. More than that, such critical issues for our democracy deserve to be scrutinised fully and as effectively as possible, not as bolt-ons to other committees; it suggests a lack of seriousness about the present constitutional moment combined with a disregard for parliament's ability to act otherwise. It also directly strikes at the Wright reforms introduced in 2010, which have helped strengthen the power of the legislature vis-a-vis the executive by, for example, introducing elected chairs of select committees. Abolishing the PCRSC goes against the grain of these reforms, showing contempt for parliament in the process.

The broader constitutional moment make this decision all the more regrettable. The publication only yesterday of A Constitutional Crossroads: Ways Forward for the United Kingdom by the Bingham Centre for the Rule of Law highlights how we stand at a critical juncture – and how informed scrutiny and thought can help us better charter the UK through unclear waters. We will need such contributions more than ever as the constitutional underpinning of the UK is debated, tested and reshaped in the years to come, not just regarding Scotland, but also with the growing momentum towards thoroughgoing English devolution. The Political and Constitutional Reform Select Committee has played that role before; that it will not continue to do so is a loss to our democracy that we can ill afford.

Given this, it is critical that MPs and the whips of all parties speak out in favour of its re-establishment, lest the executive run riot during the critical constitutional period ahead. The pressure of civil society in all this will be vital. More broadly, though, this incident clarifies the case for a constitutional convention to examine properly, in the round and with the input of citizens, how the exercise of state power is to be organised in an increasingly territorialised UK. A closed-room constitutional carve-up will lack legitimacy and staying power: the issue must be settled in the open, with broad public participation and proper parliamentary scrutiny.

The common refrain, of course, is that democratic reform is too arcane, too abstract and too remote from the everyday struggles of politics and daily life – a Westminster parlour game. Yet how we organise our democracy and its institutions fundamentally shapes how we live together, how our economy is organised, and how power operates: it is the essence of politics, not the ephemera. It is therefore time that we took democracy seriously and work to ensure that our institutions reflect that spirit.