BOSTON (AP) — As Boston police prepare to launch a body camera program after months of resistance, the city’s largest police union is asking a judge to issue an injunction to temporarily halt the initiative.

A hearing is scheduled in Suffolk Superior Court Tuesday.

The Boston Police Patrolmen’s Association claims the city violated an agreement when Commissioner William Evans assigned 100 officers to wear the cameras after no one volunteered.

The two sides had reached an agreement in July calling for 100 officers to volunteer to wear body cameras for six months.

A union lawyer says the injunction request seeks to stop the city from implementing the program until the two sides can renegotiate.

Activists have called for police body cameras since the fatal shooting of Michael Brown in Ferguson, Missouri, in 2014.

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