Amnesty International has accused Britain of putting asylum seekers' lives at risk by using out-of-date and inaccurate information to decide whether they should stay or be sent home.
Amnesty this morning said the Home Office was making ill-considered decisions about people's credibility and failed to properly consider complex torture cases.
"Getting an asylum decision wrong is not like a clerical error on a tax bill or a parking fine. Wrongly refusing someone's claim could mean returning them to face torture or execution," Amnesty International UK Director Ms Kate Allen said. "These are life or death decisions and the Home Office is getting one in five of them wrong."
But the Home Office said it had taken several steps to improve the quality of the information it uses, including using Amnesty's own reports, working with the United Nations' refugee agency and making more fact-finding visits to countries with large numbers of applicants.
For its report called Get it Right: How Home Office decision making fails refugees, Amnesty studied more than 170 asylum refusal letters received by the group.
It called on the government to improve training of asylum caseworkers and set up a body to provide better information on asylum seekers' countries of origin.
Asylum and immigration issues returned to the headlines last week after 19 Chinese migrants, who were sent to gather shellfish in Morecambe Bay were drowned by rising tides.