The threat to arrest for obstruction is widely used by the police at demonstrations.
Under the Police Act 1996 s89 it is an offence to assault, resist or wilfully obstruct a constable in the execution of his/her duty.
Willful obstruction of a police officer means doing any act which makes it more difficult for the officer to carry out their lawful duty e.g. stopping them doing something, de-arresting someone, deliberately misleading them, or giving a false name and/or address.
Being limp makes it more difficult for a police officer to move you, and is not obstruction.
Whilst this isn’t the heaviest of charges, it looks worse than the offences covered so far.
There are more rare incidents when someone is accused of assaulting an officer. Both are considered at magistrate’s courts only. Note that simply refusing to give your details is not obstruction. ‘Assault’ means intentionally or recklessly causing a police officer to sustain immediate unlawful violence. It is not necessary that there is any injury to the officer.
It must be proved that a person has assaulted a police officer in the execution of their lawful duty.
Sentencing starting point: Community Punishment Order