VIRGINIA BEACH, Va. (AP) – The city of Virginia Beach may soon commission an independent investigation into the mass shooting that claimed 12 lives last month, but the findings might not come out quickly enough for some victims’ families, state lawmakers and city officials.

City Council members delved into a debate Tuesday over how a third-party probe would proceed. One contentious issue is whether police would have control over when the separate investigation could begin.

One proposal before the council says the probe would commence only after police provided written assurance that it would not interfere with their own investigation.

Council members clashed over the desire for answers and the need for police to finish their investigation.

The shooting occurred May 31 when city engineer DeWayne Craddock opened fire in the municipal building where he worked.