Question to the Home Office:

To ask the Secretary of State for the Home Department, on how many occasions individuals have been held on police bail for over three years in the last (a) one year, (b) two years, (c) three years, (d) four years and (e) five years.

The Home Office collect and publish data on use of various police powers, including pre-charge bail. Information has been collected on the number of individuals on pre-charge bail and the length of pre-charge bail since April 2017. The data are published as part of the annual ‘Police Powers and Procedures’ statistical release, available in Annex B:
https://www.gov.uk/government/collections/police-powers-and-procedures-england-and-wales

However, data on other types of police bail are not available.