http://www.legislation.gov.uk/ukpga/2003/44/section/7/notesPoliceSentencingLegislationArrestPrisonsExplanatory Notes to Criminal Justice Act 2003Home OfficeKing's Printer of Acts of Parliament2020-04-20 44 20th November 2003 123 This provision extends the scope for an officer of at least superintendent rank to authorise detention without charge up to a maximum of 36 hours. As the law currently stands, an officer of superintendent rank or above can extend detention without charge up to an overall period of 36 hours if satisfied that detention is necessary to secure, preserve or obtain evidence, that the investigation is being conducted diligently and expeditiously and that the relevant offence is a serious arrestable offence. Serious arrestable offences are defined in section 116 of PACE and are either offences which are specified to be “always serious” (e.g. murder) or offences which give rise to serious consequences. 124 The amendment will allow detention to be extended for up to an overall period of 36 hours where the relevant offence is an arrestable offence, provided the other conditions are satisfied. Section 24 of PACE defines an arrestable offence as (a) any offence for which the sentence is fixed by law, (b) any offence for which a sentence of imprisonment of 5 years or more may be imposed or (c) any offence specifically listed in Schedule 1A to PACE. 125 This broadened capacity for extended detention without charge will assist the police in dealing effectively with a range of offences, for example robbery, where it will sometimes be extremely difficult or impossible to complete the necessary investigatory processes within 24 hours.