So far the Minneapolis police have said little. The officer involved was Mohamed Noor, 32, a Somali-American with only a couple of years on the force who is now on paid administrative leave.

The police said no weapon was found at the scene. Mr. Noor and the other officer who arrived with him did not turn on their body cameras, and the authorities have said that video cameras inside their patrol car also did not capture the shooting.

Both Mr. Noor and his lawyers have declined to comment. But the Minnesota Bureau of Criminal Apprehension did provide one small detail on Tuesday night, saying Mr. Noor’s partner reported hearing a loud sound near their car shortly before the shooting — suggesting that the officers may have been startled.

In Australia, what’s driving much of the outrage is the extreme response, and just how common it seems to be. Ms. Damond was one of more than 500 people shot and killed by the police in the United States this year. And even when population differences are taken into account, that is far more than in Australia.

Specifically, the number of people killed this year by the police in the United States is about five times the 105 killed by the police in Australia from 1989 through 2011, according to an extensive government study that is more comprehensive than anything compiled by law enforcement officials in the United States, where police departments are not necessarily required to report fatal shootings to any central authority.

Put another way, about four people are fatally shot by the Australian police each year, or one per six million people; in the United States, it is about one in 333,000, and that disparity is integral to the sense of bewilderment and fury in Australia.