http://www.guardian.co.uk/eu/story/0,7369,1335533,00.html
"'We are not obliged to have any of the European rules here. But where we decide in a particular area, for example to halt the trafficking in people, for example to make sure that there are proper restrictions on some of the European borders that end up affecting our country, it allows us to opt in and take part in these measures.'"
