Social justice activists are suing the City of Rochester over the emergency order limiting late-night gatherings.
The group Free the People ROC wants a judge to block the order from being enforced.
The order by Mayor Lovely Warren prohibits gatherings outside of five or more people between 11 p.m. and 5 a.m.
She said the purpose was to curb the rash of shootings that killed eight people since June.
On the first night of the order, police made numerous arrests for violations of the order during a protest against it.