Shortly after becoming Premier last June, Mr Brown declared:  If you commit a crime, you will be deported. You play by the rules or face the consequences.       Half of the foreign prisoners released last year were allowed to walk straight back onto Britains streets, 4,150 burglars, muggers and other convicts remained in the UK.  Many were allowed to stay because of human rights laws or an EU directive making it harder to remove criminals from other European nations.  Figures reveal that 8,350 foreign nationals were freed from UK prisons in 2007.  But, according to the Home Office, only 4,200 were deported or removed. This figure also includes offenders released in previous years.