This chapter addresses perhaps the most important debate in the literature: that the law, and in particular the development of human rights law and practice, has funnelled migration policy making in a particular direction. The argument proposed here is that there is a ‘legal bottom line’ and policy cannot circumvent it.

It also discusses the legal constraints on policy making, such as ensuring non-discrimination in policy delivery. In the UK, legal redress is possible if policies are implemented outside of the law, outside the powers of the public body, or are enacted unreasonably. The chief mechanism for this is judicial review, and its effect on migration policy is discussed more fully below.

International law

The general migration literature has long been cognisant of the importance of legal norms in circumscribing policy action (Guiraudon and Joppke, 2001). Yasmin Soysal has claimed that the development of international law has reached a point where policies must treat citizens and non-citizens in similar ways (as human beings). She argues that liberal democratic states are bound by ‘post-national citizenship’, which ‘reflects a different logic … what were previously defined as rights become entitlements legitimized on the basis of personhood’ (Soysal, 1994, p 3). David Jacobson similarly argues that developments in human rights curtailed the ability of states to regulate citizenship and the rights of aliens. In his view, it is residence in a territory (as a human being) rather than membership of a national community (as a citizen) that affords rights (Jacobson, 1997).

These claims, however, are muted when applied to the UK. The consensus view of the political science literature is that the (overly) powerful executive has generally ridden over the rights of migrants, a view completely at odds with the Soysalian proposition (see, for example, Joppke, 1999). This has been because the UK executive is particularly powerful (it lacks, for example, a written constitution) and has therefore been able to develop policy that treats migrants differently from citizens.

Unlike globalisation, there are few mentions of legal constraints in government documents on migration, whether they are White Papers or policy strategies, and Labour politicians have sometimes caricatured the legal establishment as an overly liberal bugbear, intent on slowing and blunting needed reforms.