The crucial words are "if they suspect". They can just say they didn't suspect after preliminary investigation and ignore accusations of crime at any level.I thought that police only had discretion over summary matters and low level crime such as low value theft, minor criminal damage and minor assault etc.They are duty bound to investigate if they suspect that an offence has taken place and to gather evidence. The CPS then decide when and if charges are brought.
Current instances in the news probably sitting different sides of the fence of guilt/innocence are those of Sir Cyril Smith and Sir Cliff Richard.
In both the police chose not to take any action on implications of serious crime.
In the one Tom posted about, the potential offender claims an oversight. That gives the police the option of ignoring or warning on the basis of there being no intention to break the law.
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