The son of the West Australian police commissioner has pleaded guilty to three violent charges committed against a woman, while three other offences have been dropped.

Russell Joseph O’Callaghan appeared in the West Australian District Court on Thursday via video link from Casuarina Prison.

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He pleaded guilty to assault causing bodily harm, indecent assault and threatening to kill the woman.

The court heard O’Callaghan had removed the woman’s underwear and threatened to rape her.

Charges of threatening with intent to influence and deprivation of liberty were dropped, while a charge of sexual penetration without consent had been committed to the District Court, but never indicted.

O’Callaghan will face a sentencing hearing on January 5.