How much time do you give a knife-wielding man to stop, before you shoot?

A Seattle police officer shot and killed a knife-wielding man in the street shortly after he rammed a patrol car on I-5 July 17.

Days later, the Seattle Police Department released a video of the officer’s car being rammed and the fatal shooting.

The officer shot the man, Samuel Smith, after announcing his presence and informing him he was being recorded. The suspect ran toward the officer, with a 10-inch knife held over his head.

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As the officer backed away from Smith, he fired several shots into the man, killing him.

Investigators are now reviewing the case, gathering evidence and interviewing witnesses.

Typically, people will question whether that officer’s decision was justified, KIRO Radio’s Don O’Neill said. Maybe not so much in this case. It’s dark out, the officer is alone and the suspect has already proven himself dangerous.

“The next thing you know, this made man comes after this officer with a knife,” Don said. “I’m just glad this officer is alive.”

That doesn’t mean the critics will be silent. Between the time the officer makes contact with the suspect to shooting him, is about eight seconds. People are going to wonder why the officer didn’t give the man more time to drop the knife, KIRO Radio’s Ron Upshaw said.

“From the second he says ‘good morning’ to the shots, is about eight seconds,” Ron said.

But what was the officer supposed to do? The man was running at him with a knife.

“The guy has a knife over his head,” Don argued. “If [the officer] waited another half-a-second he would have been dead.”

The officer should receive a medal, not be criticized, Don added. He is currently on paid leave.