The UK Should Leave the European Union

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.We need to co-operate against global crime and terror

The main advantage of Europol is that it enables criminals that cross borders to be tracked and arrested easily by a multinational force. However, if is considered that Britain is an island, the likelihood of criminals crossing our borders is quite low, thus rendering the major advantage of Europol somewhat irrelevant.  
 
If the aims of the UK are to fight global terror then surely it would be of greater benefit to strengthen relations with the United States where there is a far stronger focus on tackling this issue.  

...We need to co-operate to fight the increasingly global threat of crime and violence. Europol is an effective multinational police and security force and leaving Europe would deprive us of its benefits.