From employment rights to environmental standards, many of the most cherished legal protections in British life could be rewritten at will by the government under sweeping new powers proposed by the “great repeal bill”.

David Davis, the minister in charge of shepherding this giant legislation through parliament, insists such authority will only be used to carry out whatever “technical changes” are deemed necessary to keep British law functioning as he negotiates the UK’s departure from the European Union.

But campaigners and lawyers from both sides of the political spectrum have sounded alarm bells about the precedent, practicalities and purpose of a bill described as “one of the largest legislative projects ever undertaken” by the House of Commons library.

The great misnomer

The first and perhaps most cosmetic concern is that the exercise has been deliberately misnamed. Though styled after the radical great reform bill of 1832, it could, as even supporters like Davis concede, just as easily have been called the “great continuity bill”, since it largely transposes existing EU law rather than aiming to introduce new rules.

“That doesn’t have the same appeal,” the Brexit secretary told MPs recently when asked if it would be more accurate to describe the legislation as the great conversion bill.

It would have played a more radical role in its original conception, since its first provision is to overturn the 1972 European Communities Act and therefore formally restore parliamentary sovereignty at the moment that Britain leaves the EU.

But since a high court challenge forced the the government to ask MPs to vote for Brexit when it invoked article 50, this symbolic parliamentary handover is arguably already under way.

Instead, no matter what you call it, the great repeal bill has become home to the plumbing rather than the poetry of the Brexit process: unpopular with remain supporters for obvious reasons, but also hardly the bonfire of regulations once imagined by leavers.

Henry VIII powers

The desire for continuity does not mean it is without controversy. More substantive worries are growing over the way government ministers plan to convert the European “acquis” into UK law.

With so much to get through in so little time, not everything can be covered in the initial bill, so the government proposes using statutory instruments to “create a power to correct the statute book where necessary, to rectify problems occurring as a consequence of leaving the EU”.

To make matters worse, it needs enough flexibility to “support a scenario where the UK left the EU without a deal in place”, suggesting a possible avalanche of last-minute changes as Brexit talks fall apart in the final hours before 30 March 2019.

Though Davis insists there is no intention to weaken rights or substantially change regulation along the way, critics have compared the powers to those assumed by Henry VIII in their ability to overturn primary legislation through the use of less accountable secondary legislation.

The Labour MP Clive Lewis has vowed to fight this “Henry VIII clause”, warning: “If we fail, and allow Theresa May to assume the powers of a renaissance monarch, our divisions will grow and our future will look bleak.”

The Green MP Caroline Lucas said: “Far from being ‘technical’, the great repeal bill is a huge attack on our democracy. The government wants unlimited power to amend law.”

Not radical enough?

It is not just politicians on the left who are uncomfortable about the wholesale rewriting of regulation.

Though most Tories support the aims of the bill, many are using its passage to underline their desire to eventually scrap many of the EU rules it will transfer. For example, Iain Duncan Smith, used an editorial in the Daily Telegraph this week to launch a campaign for a bonfire of EU regulation once the bill is out of the way “to put Britain on a radically different course”.

No one is yet suggesting getting in the way, but if life gets trickier for the government it may not be able to take the enthusiasm of its right-wingers for granted, and they could use the power to start their bonfire of regulations early.

For now, the white paper underlines that the case law of the European court of justice and text of EU treaties will continue to hold sway, and indeed precedence, over UK law.

“Above all, [the white paper] implicitly confirms that there can be no clean break from the EU,” said Ashurst competition lawyer Catherine Hammon. “It loudly celebrates taking back of control and reasserting British sovereignty, but there is a clear acceptance in the detail that in practice this is going to be a very gradual process, and there will be no immediate bonfire of EU derived-regulation.”

Davis says in the introduction to the white paper: “Taking back control does not require us to do everything overnight.”

Civil liberties

There are few clearer examples of this than the fact that some civil rights lawyers took comfort from a line in Davis’s statement where he pledged that: “The UK’s withdrawal from the EU will not change the UK’s participation in the European convention on human rights and there are no plans to withdraw from the ECHR.”

Before the EU referendum, Theresa May, in her role as home secretary,