Peers know the Rwanda bill is flawed and dangerous. We must use every power to oppose it | Simon McDonald

So far this year, the House of Lords has debated the safety of Rwanda bill for more than 40 hours. Immediately before Easter, the Lords passed a second set of seven amendments and returned the bill to the Commons (which had earlier rejected the first set of 10 amendments). The Commons will consider those amendments when parliament returns from its Easter recess tomorrow.

The debate in the Lords has highlighted the fundamental flaws of the legislation, legally and constitutionally. But the government believes that “stopping the boats” is important enough to override the UK’s traditional respect for human rights; it argues that the scheme will have such a powerful deterrent effect that potential asylum seekers won’t cross the Channel.

Deterrence works in one of two ways. The more powerful is the certainty of unpleasant consequences when you do something. The UK-Albania communique, signed in December 2022, falls into that category. Albanians who claim asylum in the UK now know that they will be returned to Albania; they have substantially stopped coming.

Being uncertain that unpleasant consequences will not follow exerts a less powerful but sometimes still effective deterrent effect. The government hopes the Rwanda scheme falls into this category. And yet debate has revealed facts that undermine their case. First, the Home Office minister, Lord Sharpe, revealed that about 55,000 asylum applications were lodged in the last nine months of 2023. Second, ministers failed to deny reports that Rwanda has agreed to take just 300 refugees in the first three years of the scheme’s operation. So, a refugee’s chances of deportation are minimal. Very few potential asylum seekers would be deterred by such odds, having already journeyed thousands of miles and overcome numerous challenges.

The scheme would also be astronomically expensive: the National Audit Office puts the costs at £541m. The cost for each refugee sent to Rwanda would be about £1.8m over three years. As Lord Carlile has observed, it would be cheaper to put them up at the Ritz.

For this doomed venture, the government is asking parliament to pass legislation that is extraordinary in two ways. First, the bill declares as a fact that Rwanda is safe enough to provide shelter for vulnerable people fleeing persecution in their home countries. It is true that Rwanda has seen astonishing progress since the genocide that began 30 years ago this month. But it is not safe. President Kagame does not tolerate dissent. And the best our government can manage when challenged over the treatment of the LGBTQ+ community is that Rwanda does better than its neighbours, some of the world’s most notoriously hostile countries towards LGBTQ+ people. Rwanda is also embroiled in the civil war in eastern Congo; no one in Kinshasa considers Rwanda a safe country to do business with.

Repeatedly, ministers cite the signature of the UK-Rwanda treaty as clinching proof that Rwanda is safe. Kigali has made a series of promises that parliament is invited to take at face value. But signatures are cheap. Naivety is the second worst failing of diplomats. Ronald Reagan was guided by the principle “Trust but verify”. The House of Lords international agreements committee concurs and has set out 10 tests it believes need to be passed before the treaty can safely come into force. The government rejects the need to verify.

Second, the bill states that British courts must accept that Rwanda is safe; courts can neither question that view now nor in the future in the light of new evidence that Rwanda may no longer be safe. From time to time, governments set out controversial facts in legislation. To date, it has been possible to test such facts in court; that happened, for example, with the Asylum and Immigration Act (2004) when the courts upheld the government’s view that Rwanda could be considered a “safe third country”.

This time is different. The courts will be told unequivocally that they cannot question the government’s view. This is unusual but not unprecedented. Lord Hoffmann reminded the Lords of the last such case, the Acte for Poysoning (1531). Henry VIII had a pathological fear of poisoning. Originally the bill had two provisions: to treat all cases of poisoning as treason and to stipulate death by boiling for anyone found guilty. At the last minute, he added a third clause, after two people died following a dinner party given by the bishop of Rochester in February 1531. The bill found Richard Roose, the cook, guilty of poisoning. Royal assent was given on 31 March and Roose boiled to death on 15 April.

Even at the time, parliamentarians were uneasy; the act was used in only one other case before its repeal in the first year of the reign of Henry’s successor. But the stain on the country’s reputation is remembered 493 years later. The government wants to repeat Henry’s error.

Hypocrisy is the worst failing of diplomats. Throughout my career in the Foreign Office, British diplomats used to lobby governments about the importance of the rule of law, respect for the independence of the courts, and the balance of power between different branches of government. With this act, the UK undermines the case we have traditionally made. Labour has undertaken to repeal the act should it be elected, but the damage will have been done. Last month, the president of the European court of human rights said the behaviour of three European countries was causing her concern: Russia, Turkey and the United Kingdom. That’s not a club the UK should belong to.

A horrible sense of inevitability hangs over the final stages of this process. The Commons will reject the seven Lords amendments on 15 April. The Lords might have another go, perhaps focusing on just two amendments the next day; the Commons would reject them the day after. By Thursday 18 April, the deed will be done. Members of the appointed chamber will comfort themselves with the knowledge that they raised objections but, despite their cogency, did not feel able to defy the repeated wishes of the elected chamber.

But it does not have to be that way. The Lords can resubmit one or two of its amendments in identical language to amendments already rejected by the Commons. Usually the Lords accepts the Commons’ specific rejection, and tries slightly different language in the hope of persuading MPs. When an amendment in identical language is resubmitted, the Commons and the government have a choice: either accept the repeated view of the House of Lords, or lose the bill entirely. The issues at stake are important enough for the Lords to confront the Commons with precisely that choice.

• Lord McDonald of Salford was permanent secretary at the Foreign Office, 2015-2020, and is now a crossbench peer