Migration Watch's Alanna Thomas has called for the Home Office to overhaul its system to deal with asylum claims.
This follows reports that one in three claims for asylum have been made by people who are either in the UK illegally or have overstayed their visas. A number of critics have suggested this is an abuse of the system.
Thomas, the chief executive of the think tank, has explained how the system allows claimants to vanish.
"The problem is that clearly some people want to avoid removal," she told Julia Hartley-Brewer. "A third of all claims are only made by people once they encounter immigration officers.
"Some people will be granted asylum, but most are only claiming asylum at that point to avoid deportation.
"There's a lengthy process to go through to avoid this - the Home Office decides the case and there's an appeals option, so there is time to go back into the shadows.
"There needs to be an enforcement officer to verify them."