What would happen if the UK government simply ignores the ECHR and proceeds with the Rwanda relocation scheme?

Question

As explained in the answer to Would there be any economic consequences if the UK were to leave the ECHR?, leaving the ECHR over the Rwanda plan could potentially upset the Good Friday agreement and is thus seen as a bad option for the UK government. But if they just... ignore the court's decision on this matter? The ECHR lacks the ability to enforce any of its decisions so why not just... ignore their judgements on the Rwanda question entirely, without officially leaving the court's jurisdiction?

They could still abide by all other ECHR rulings but declare that henceforth any rulings related to matters of asylum will be ignored.

Update: looks like this will now happen, thanks to a new law.

Answer 1

The government would be breaking the law of the UK. And so could be sued for damages in UK courts.

It is different if Parliament tells the government to ignore the ECHR, for example by amending the Human Rights Act. However this is what "withdrawing from the ECHR" means. Either you accept its jurisdiction by incorporating it lock stock and barrel into national law, or you leave it. You can't pick and choose.

More generally, the "Rule of Law" is one of the "British Values" that all schoolchildren must be taught about. So simply ignoring UK law is contrary to the the government's stated policy.

Answer 2

They could still abide by all other ECHR rulings but declare that henceforth any rulings related to matters of asylum will be ignored.

International repercussions could they'd be suspended from CoE for that. Unlike the EU, where getting out is entirely voluntarily, a country can actually get expelled from CoE, although that's no more than a badge of shame, I guess.

Less likely, but still possible, other signatory countries might stop cooperating with the UK on asylum/migration matters even on a bilateral level. (They have some such agreements with France etc.) And possibly on other matters.

Suddenly turning a blind eye to boats departing from their shores is something quite a few countries have done, although generally not in Europe, but at the edges of it.

OTOH, France might have recently established a precedent for ignoring the EC[t]HR in some such matters. (Hat tip to Obie 2.0 for pointing me to this):

The man, who French authorities accuse of being a radical Islamist, was deported to Uzbekistan on 15 November. Paris expelled him in defiance of the Strasbourg-based European Court of Human Rights, which ruled in March he risked danger in his home country if returned.

“I decided to send him back to his country, regardless of everyone’s decisions. We will do everything so that he cannot come back,” Gérald Darmanin told CNews.

The ECHR had issued an “interim measure”, an urgent ruling only handed down when it deems there is imminent risk of irreparable harm to a plaintiff.

The Council of State, France’s top administrative court, then said on 7 December the French government should assist the man to return from Uzbekistan in order to implement the ECHR ruling. [...]

“The ECHR must understand that it is issuing rulings in a terrorist crisis situation which did not exist when its rules were drawn up,” Darmanin told the JDD newspaper.

After teacher Dominique Bernard was killed by an Islamist hailing from Russia’s northern Caucasus in mid-October, Darmanin vowed to defy ECHR rulings blocking expulsions, saying “protecting the French public is more important than these rules”.