[Memo to self: Been banging on about Europe too much recently. Time to move on to some other issues. What else has been in the press? Ah yes...]
Controls orders infringe upon the liberties of British citizens without the people concerned having any opportunity to test those restrictions before a court. They only exist because the previous regime, which quite properly imposed restrictions on the movement of dangerous foreigners, was struck down as a violation of Human Rights.
We could move to a more liberal system by repealing the Human Rights Act and preferably also repudiating the illiberal doctrine of "human rights". But that would only have limited impact if we did not also stop accepting the judgements of the European Court of Human Rights (ECHR). Of course, under the Lisbon Treaty it would not be possible to limit one's acceptance of ECHR judgements whilst remaining a member of the EU, so in order to abolish control orders and return to a more liberal system in which we merely restricted the movement of dangerous foreigners but insisted that to restrict the liberties of British citizens one would require a trial, we would need to renegotiate our position within the EU.
[Drat! Was supposed not to be talking about EU. Must try harder. Some other topic, perhaps. What else has been being discussed? Ah, yes...]
The government's problem has arisen because it has been subject to a ruling under the Human Rights Act. If it wants to get out of it, it would need to repeal the Human Rights Act and to withdraw from (or restrict its commitment to) the European Convention on Human Rights, which since the Lisbon Treaty would require renegotiating our position within the EU.
[Double drat! Not doing very well, here. Will shut up and try to think about something other than criminal justice issues, since these are now heavily influenced by the EU (via the ECHR as discussed here and through other routes) - as noted by the 2010 Conservative Manifesto, which was a key reason we committed to renegotiating our position within the EU in respect of criminal justice policy.]