Lawyers investigate whether Hannah Thomas could sue police over alleged excessive use of force at Sydney protest

Critical incident investigation declared into arrest of former Greens candidate who says she could lose sight in right eye

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Lawyers are investigating whether protesters could sue New South Wales police over alleged excessive use of force during a pro-Palestine protest in Sydney, after which the former Greens candidate Hannah Thomas said she could lose sight in her right eye.

Thomas, 35, who ran against the prime minister at the federal election, was arrested at the Belmore protest which was attended by about 60 people on Friday. She was subsequently taken to hospital and underwent surgery.