A fourth man is standing trial in relation to the drugging and sexual assault of women at a central Christchurch bar, after an investigation from 2018.

Two men have already been found guilty on almost 70 charges of stupefying and assaulting more than 20 women, and a third guilty of offering to supply an illegal drug.

The Herald's Anna Leask says the fourth man successfully argued to have allegations against him heard separately.

"It should be finished by midday tomorrow, given it's one charge and it's judged alone, meaning there's no jury. It's moving very, very quickly."

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