The government does not know how much its new small boats bill will cost or if it will achieve its core aim of deterring Channel crossings, an official assessment has found.
Documents published over three months after the Illegal Migration Bill was presented to parliament estimated that it will cost £169,000 to deport each asylum seeker.
The Home Office refused to publish the payments agreed with the Rwandan government, citing “commercial sensitivities” as a Court of Appeal ruling on the scheme looms.
It said it was “not possible” to assess whether changes backed by Rishi Sunak and Suella Braverman would be value for public money, because “it is not possible to estimate with precision the level of deterrence that the bill might achieve”.
Officials said that making a migrant decide against a small boat crossing could save eventual costs of £106,000 in the UK, but “the academic consensus is that there is little to no evidence suggesting changes in a destination country’s policies have an impact on deterring people from leaving their countries of origin or travelling without valid permission”.
Estimated calculations showed that it will still be more expensive to deport asylum seekers than process them in the UK, and there are currently no operational deportation agreements for asylum seekers.
“There is a risk that the practical complexities of the bill mean the bill will not be fully delivered,” the document said. “Any deterrence impact relies on the policy working as intended, with sufficient capacity to detain and remove an appreciable proportion of individuals in scope to a safe third country.”
It also warned that the laws could cause “unintended behavioural changes from migrants”, including people switching from small boats to lorries, other clandestine routes or fraud and overstaying visas.
The economic impact assessment warned of a raft of new costs stemming from the bill’s legal duty to detain and deport all small boat migrants, regardless of the merit of asylum or modern slavery claims.
They include the costs of increasing detention capacity, hiring and training more civil servants, paying private companies huge sums to “escort” people on deportation flights and increased legal challenges.
It comes after The Independent revealed that Home Office staff are already being pulled off the huge asylum backlog to re-train for the expected implementation of the bill in September.
Suella Braverman was grilled on the delay to the assessment when she appeared before parliament’s Home Affairs Committee earlier this month, with MPs and peers angry at being made to vote on the bill without knowing its costs.
The home secretary said there were “many unknown factors” involved, including legal action on the Rwanda scheme, but committee chair Dame Diana Johnson said the position was unacceptable for a bill “that is three quarters of its way through the House of Lords”.
During a debate on the bill earlier this month, a government minister said they could only be sent to countries where Britain has struck “an agreement to take them back”, adding: “That is not at present the case, except in relation to Rwanda, but it may in future be the case in relation to other countries.”