The police watchdog has found officers should not have used force against a woman worried about her teenage son at an out-of-control Hamilton party.
The party was shut down by police in riot gear in January last year after complaints from neighbours and noise control officers.
The woman, who was not at the party, had been questioning police actions loudly on the street when they moved to push her out of the way with a shield.
The Independent Police Conduct Authority found that was not a good enough reason for officers to use force against her.
Officers described the force as a "light push" or a "nudge" but the authority said video evidence showed they pushed her with "some force" at least twice.
The authority said police were justified in shutting down the party.
