UK Immigration Service grades are/were reflective of the legislation that stipulates that the decision to refuse a person leave to enter the United Kingdom is taken by an Immigration Officer only with the authority of a Chief Immigration Officer or an HM Immigration Inspector. The decision that a person inside the UK is in breach of immigration law and liable for administrative removal or deportation can be taken by an Immigration Officer or a caseworker of Executive Officer grade or above acting on behalf of the Secretary of State, with the authority of a Chief Immigration Officer or Higher Executive Officer. The removal of such offenders may only be enforced with the authority of an HM Inspector or Senior Executive Officer. Immigration Officers also have the power to deal with immigration offenders under the criminal proceedings part of the Immigration Act 1971 and prosecute through the Criminal Justice System.