 The passing of the act supersedes the process where the Customs Commissioners would designate officers as customs officials.Designated Immigration Officers (DIOs) are designated by the Home Secretary, and only if they are fit and proper for the purpose, and suitably trained.Under Section 2 of the UK Borders Act, DIOs can detain any person without arrest in a port in England, Wales or Northern Ireland if they think that the individual may be liable to arrest by a constable for any offence under Section 24 of the Police and Criminal Evidence Act 1984 or Article 26(1), (2) or (3) of the Police and Criminal Evidence (Northern Ireland) Order 1989, or if there is a warrant for their arrest.