Policing and Crime Act 2017

The Policing and Crime Act 2017 (c. 3) is an act of the Parliament of the United Kingdom. It received royal assent on 31 January 2017.
The act enacts various changes to existing rules involving PCCs, complaints through the IPCC, amendments to PACE 1984 etc. One notable change involves the expansion of powers to police staff and introduces voluntary police community support officers (PCSOs). It is also expands the powers of a PCSO to "any power or duty of a constable, other than a power or duty specified in Part 1 of Schedule 3B (excluded powers and duties)". Part 6 of the act brings clarity to the classifying guns under the Firearms Act 1968, based on recommendations from the Law Commission.
Another change relates to police bail, which can now only be authorised by an officer of inspector rank or higher (so normally a suspect will now be released without bail if not charged), and extending this period is now only possible once by authorisation of a superintendent officer, or again by a magistrates' court; previously it was possible for police to effectively restrain a person indefinitely by extending the bail period every 28 days.
Controversially this has led police forces to adopt an alternative method of 'releasing under investigation' with no time limits or conditions, requiring a suspect to respond by post. 
The act also implements the Alan Turing law, offering an automatic pardon to men convicted for homosexual acts that are no longer considered criminal offences.