A crowd of 100 people wreaked havoc in downtown Portland, Oregon, this week - smashing storefront windows, lighting dumpsters on fire and causing at least $US500,000 ($A674,043) in damage - but police officers didn't stop them.
Portland Police Bureau officials say that's because of legislation passed by Oregon lawmakers this year, which restricts the tools they can use to confront people vandalizing buildings and causing mayhem.
"The reason that we did not intervene goes back to ... the restrictions placed on us in a crowd control environment," KOIN reports that Portland Police Leuitenant Jake Jensen said in a neighborhood meeting Thursday.
Residents frustrated by the latest round of destructive demonstrations Tuesday questioned whether that meant anything goes now in Portland.
"Does that mean we are now like a lawless city?" Linda Witt asked during the meeting with police.
Jensen replied saying people can still face consequences later.
The legislation in question prohibits the use of things like pepper spray and rubber bullets for crowd control.
However there is an exception - when the circumstances constitute a riot and if the officer using the chemical incapacitant reasonably believes its use is necessary to stop and prevent more destructive behaviour.
"The law clearly allows Portland Police to use effective tools necessary to control violent crowds," House Minority Leader Christine Drazan told The Associated Press on Friday.
"However, activist attorneys are deliberately misinterpreting legislation to prevent police from intervening. They have no business putting law enforcement and community safety at risk."
Portland Police Sergeant Kevin Allen told AP that: "until we have some clarity on the bill we have to follow the most restrictive interpretation of it."
Portland has seen ongoing, often violent protests since the murder of George Floyd by police in Minneapolis. Some activists have complained that the police have been heavy handed in their response.
On Tuesday, police say 35 separate locations were targeted - including banks, retail stores, coffee shops, and government buildings.
Authorities say although police did not directly intervene, officers did give direction to disperse over a loudspeaker and a Mobile Field Force moved in, at which point the crowd splintered.
Australian Associated Press