Rwanda is a country that “imprisons, tortures and murders” its opponents, including those who have already fled the country, the UK’s supreme court has heard. Raza Husain KC, representing asylum seekers challenging the Rwanda policy, told five senior judges of human rights breaches in the east African country. He said opponents of the Rwandan government were at risk of police violence and “absolute repression”. Addressing the judges on the first day of a three-day hearing to determine the legality of the Home Office’s controversial policy, Husain said: “Rwanda’s asylum system is woefully deficient and marked by acute unfairness. The secretary of state [Suella Braverman] has an uphill task in seeking to defend Rwanda’s asylum system. “She does not dispute the state of Rwandan asylum system significantly but rather seeks to ignore it.” The Home Office is bringing the challenge after the court of appeal ruled in June that the multimillion-pound deal – under which some people who arrive in the UK via irregular means would be sent to the east African country to have their asylum applications processed – was unlawful. The judges are hearing arguments over whether two appeal judges were right to find there was a “real risk” asylum seekers could be returned to their home country and face persecution when they may have a strong asylum claim. Husain told the court Rwanda was an “authoritarian, one-party state” that “imprisons, tortures and murders those it considers to be its opponents”, adding that Home Office officials had “repeatedly recorded their concerns about it”. The UK government is arguing that the scheme is lawful and safe. The UN high commissioner for refugees (UNHCR) is intervening in the case. Ten asylum seekers from a variety of conflict zones including Syria have challenged aspects of the ruling. Sir James Eadie KC, for the Home Office, told the court there was a strong public interest in taking steps to deter people taking the “perilous” journey across the Channel to reach the UK. He said the government attached “considerable importance” to its Rwanda deportation policy, adding there was “a serious and pressing need to take effective steps that will act as a deterrent to those undertaking the perilous and sometimes life-threatening journey, typically across the Channel, from a safe country”. “This is a bespoke scheme with a very clear and expressed aim,” he said. “There are detailed assurances from Rwanda regarding the processing they are going to put in place and reception arrangements. The scheme will be independently monitored.” He added that there were 36 lawyers in Rwanda who could provide legal aid to asylum seekers to assist them with their cases. Lawyers challenging the policy previously raised concerns that some asylum seekers, particularly from Middle Eastern countries, were at risk of being forcibly returned to these countries from Rwanda. Eadie told the court there would be no enforced removals to any Middle Eastern countries. In written submissions to the supreme court, Angus McCullough KC, for UNHCR, said it had “consistently expressed grave concerns” about the safety and legality of the policy. He said: “UNHCR maintains its unequivocal warning against the transfer of asylum seekers to Rwanda under the UK-Rwanda arrangement.” There is a lack of clarity about how many asylum seekers the Home Office intends to send to Rwanda if the policy overcomes the current legal and practical hurdles it is facing. Government media briefings over the weekend suggested that officials are planning to send 4,000 people to Rwanda before the next election if the policy gets the green light from the courts. However, Eadie said in court on Monday that “the system will take time to develop”. He added: “[Braverman] is well aware it will take time to build capacity. A small number is designed to get on the first plane.” The hearing, before Lords Reed, Hodge, Lloyd-Jones, Briggs and Sales, is expected to end on Wednesday, with a judgment at a later date.