BETTER late than never, MPs in Westminster have started to get their act together over Brexit. It’s a month since Theresa May made clear she intended to push Article 50 through under pre-democratic powers of Royal Prerogative. It seemed obvious that by-passing Parliament raised questions about executive power and parliamentary sovereignty. But a lack of urgency on the part of MPs allowed the Prime Minister a head start.

Perhaps Labour at Westminster believed parliamentary sovereignty was too technical to matter to voters; perhaps Labour leader Jeremy Corbyn was unsure that he wanted to challenge the Government’s determination to impose hard Brexit. There has been a concerted media campaign to undermine Parliament’s resolve by portraying critics of the Government’s approach as “whingeing” Remainers who want to reverse the EU referendum vote. This may have intimidated MPs on both sides.

However, it looks as if an incipient rebellion on the Tory backbenches has forced the Government into accepting some kind of parliamentary involvement, though we’re still in the dark about precisely what. There is talk of consultation and opportunities to vote but there is no prospect of a White Paper or parliamentary bill on the most important issue facing Parliament in half a century: the terms of Article 50. But this is not just an issue for Westminster. The Scottish Parliament’s role in the process is similarly opaque.

The Prime Minister told Nicola Sturgeon in June that there would have to be “a common UK position” involving the devolved legislatures before Article 50 was announced. Well, it has been; and there isn’t, though there are the usual noises about consultation. MSPs are will have to organise if they want to have any say in the Brexit process. But it sometimes seems the only thing opposition parties care about at Holyrood is the threat of a second independence referendum.

As the SNP convenes its conference this week it is clearer by the day that a repeat referendum on independence is off the agenda. There will be protestations by the First Minister that it “remains an option” if the UK Government pushes through hard Brexit but there can be few in any doubt that it isn’t going to be next year. What is important is ensuring that the Scottish Parliament is mobilised to protect Scotland against the the worst excesses of hard Brexit. This will require the Scottish political parties, at least the non-Tory ones, to realise they have a common purpose

At present the UK Government seems to be saying that, because all the EU laws are being retained by default in the immediate aftermath of Brexit, the Scottish Parliament needn’t worry its little head: leave it all to Westminster. But each of the powers repatriated from Brussels has to be incorporated into UK law or not, as the case may be. For example, the UK Government may decide to scrap the Working Time Directive limiting hours to 48 a week rather than repatriate it. Brussels loses the power to set VAT levels after Brexit, so which levels are going to be set in future and by whom?

Holyrood could be in line for more powers on VAT and matters like fisheries since EU boats will no longer be free to fish in Scottish waters; or will they? Who decides? Will the Scottish Government inherit the system of agricultural subsidies criticised in Europe for favouring industrial agriculture, or will policy on agriculture effectively come from Westminster because that’s where the policies are financed?

Under the so-called the Sewel Convention, Holyrood has the right to pass consent motions on any actions of Westminster that cut across Holyrood’s powers. There is no way the Repeal of the 1972 European Communities Act could not impinge on the Scottish Parliament’s powers, as the former UK Attorney General, Dominic Grieve conceded yesterday in Parliament. As hundreds of EU laws are repatriated on workers rights, agriculture, fisheries, the environment and so on, Holyrood’s powers will be hugely affected.

A fortnight ago, the Scottish Brexit Minister, Mike Russell, speculated about the result of a legislative consent motion on Brexit he evidently believed was inevitable. The primacy of EU laws on prescribed areas is written into the Scotland Act and any amendment would alter the powers of the Parliament. But the response from Number 10 was to brief that MSPs would have no say as the issue was about the constitution and that is reserved to Westminster. These are massive issues and hanging over all of them is membership of the European Single Market. Ms Sturgeon has made clear this is the Brexit bottom line as far as Scotland is concerned.

In her speech to the Tory conference, Mrs May sought to conflate remaining in the single market with reversing Brexit. But, as many of her former ministers pointed out in the Commons yesterday, including former Education Secretary Nicky Morgan, the 2015 Conservative election manifesto said Britain would remain in the single market and the Leave campaign did not rule it out. Norway is in the single market but not in the EU. As George Osborne, the former Chancellor, added: “Brexit won a majority; hard Brexit did not.”

It is not clear why Mrs May has become so hostile to the single market; she was a Remain supporter who argued that leaving would damage the economy. Has she been kidnapped by the Brexiters in her cabinet? It seems she has been persuaded that the only issue in the entire Brexit debate is immigration. At Prime Minister’s Questions yesterday she repeated her determination to reject all EU laws. This is daft: if we want to sell kettles or toasters to the single market we have to accept EU regulations and standards, as does every country.

Opinion polls suggest most voters would be prepared to accept some openness on immigration in exchange for avoiding needless damage to the economy. The idea of closing off borders is ridiculous and undemocratic. It would be absurd to tell companies they can’t employ foreign workers, though the Government has flirted with dangerously similar policies such as suggesting that firms might have to keep a register of foreign workers.

The speech by Amber Rudd provoked such a furious response that the policy was killed off within 24 hours. The U-turn allowed MPs to seize the initiative and emboldened some Tories to demand that Parliament be allowed to vote on Article 50. There was deep concern that other Tory ministers were appearing to demonise international students and even foreign-born doctors in the NHS.

This is what happens when Parliament is reduced to being a mere spectator. When prime ministers are given too much rope they generally hang themselves, as Margaret Thatcher did in 1990 with the disastrous poll tax. They need to be kept in line by a vocal cabinet and a vigilant Parliament, not just at Westminster.