The numbers of people applying for asylum in Britain has fallen by three-quarters since the peak year of 2002. According to research by Professor Tim Hatton, published in the February 2009 issue of the Economic Journal, nearly 40% of this decline in asylum applications can be ascribed to tougher policies, including stronger border controls and measures on processing claims, appeals and deportations.

But the study also shows that government policy does not deserve all the credit: after all, asylum applications have fallen worldwide. So what drove down the global numbers?

With continuing insurgency in Iraq and Afghanistan and refugee cries in Darfur, Zimbabwe and the Horn of Africa, it is hard to believe that the world has become a safer place. Yet the research suggests that it has – and trends in civil liberties, political rights and democracy point in the same direction.

Only a few years ago, the crisis in the asylum system appeared regularly in the news. Following the surge in asylum applications, which peaked in 2002 in Britain, the numbers have dropped dramatically. So what happened?

Government ministers have been quick to claim the credit for their tougher policies. But asylum applications also ebb and flow with violence and civil strife in source countries. So is it tougher policy or easing political strife that has driven down the numbers?

Professor Hatton finds that tougher asylum policies deserve some of the credit (if credit there is). But governments can only account for a third of the decline in applications across the developed world.

In Britain, the number applying for asylum fell from 103,800 in the peak year of 2002 to just 27,900 in 2007, a fall of 73%. Last year, the then minister for immigration, Liam Byrne, commented that ''stronger border controls are delivering falls in asylum claims – they''re now at the lowest for 14 years. And we are dealing with those cases faster than ever before.''

This was just one of a series of jubilant announcements that followed Tony Blair''s commitment in 2003 to slash the numbers. Since then, stiff measures have been taken on processing asylum claims, on appeals and deportations and on border controls – culminating with the establishment of the UK Border Agency.

Like Britain, most countries in the developed world have toughened their policies. The research distinguishes between policies that restrict access to borders, those that make it harder to qualify as a refugee, and those that make living conditions more uncomfortable for applicants going through the process. On average for OECD countries, the trend has been towards tougher policy in each of these dimensions.

The research finds that policies on access to borders and on processing asylum claims significantly reduced applications. But the living conditions endured by those undergoing the process had little effect.

One implication is that the need to find a balance between the deterrent effects of punitive policies on living conditions and more positive refugee integration measures is less of a dilemma than is sometimes believed. Nor is there any evidence that policies were targeted towards those from Muslim countries in the aftermath of September 2001.

Between 2001 and 2006, asylum applications to the 19 OECD countries fell by 328,000. The research finds that tougher asylum policies account for one third of this decline in applications.

But the results differ sharply between countries. In France, four-fifths of the decline is accounted for by policy compared with only a quarter for Germany. For Britain, tougher policy explains nearly 40% of the decline in asylum applications – a substantial amount, although perhaps less than government ministers would like to claim.

''The Rise and Fall of Asylum: What Happened and Why?'' by Tim Hatton is published in the February 2009 issue of the Economic Journal. A summary is published on Vox: http://www.voxeu.eu/index.php?q=node/1034