Under the Free Movement of Persons Directive 2004/38/EC, (the directive) an EEA national has the right to reside in any EU member state for up to three months without restrictions, provided that they do not become an unreasonable burden on the social assistance system of that state. Thereafter, they must be exercising treaty rights as a worker, student, self employed or self sufficient person, or be directly supported by a family member exercising such rights.
However, an EEA national may be refused admission to the UK, deported or excluded on public policy, public security or public health grounds where they represent a genuine, present and sufficiently serious threat affecting one of the fundamental interests of society. The person's age, state of health, family and economic situation, their length of residence in the United Kingdom, the person's social and cultural integration into the United Kingdom and the extent of the person's links with his country of origin must be considered in any such decision and the decision must be based exclusively on the personal conduct of the person concerned.
Current UKBA guidance states that an EEA national who commits an offence in the UK will be considered for deportation under the Immigration (EEA) Regulations 2006 if they receive a custodial sentence of 12 months or more for an offence involving drugs, violence or sexual crimes or a custodial sentence of 24 months or more for any offence. Persistent offenders falling below these criteria will also be considered for deportation.
Non-EEA nationals who do not fall to be considered under the regulations may still be liable to deportation under the Immigration Rules. These were revised in December 2012 to establish a new criminality framework and to strengthen rules relating to deportation, and can be found at: http://www.ukba.homeoffice.gov.uk/policyandlaw/immigrationlaw/immigrationrules/.