The day after we proposed a community event honoring first responders, a Seattle police officer demonstrated a degree of vigilance and preparation that exemplifies the qualities shown by many in law enforcement.

Benjamin L. Kelly, 39, has more than four years experience with the Seattle Police Department and is a military veteran. Officer Kelly showed an alert presence of mind during a situation that started out very routinely.

While on patrol, Kelly saw a car with the hood up and the engine running. He ran the license plates. The car had been reported stolen early the same day, so there was paperwork to be completed. One of the challenges in staying aware of your surroundings is that most situations present distractions.

About 48 hours earlier, four Lakewood police officers were drinking coffee and using laptop computers in a Parkland coffee shop when Maurice Clemmons opened fire.

Did any of the four victims look up and make eye contact with Clemmons as he entered the coffee shop, passing by them moments before he started shooting?

Kelly, sitting in his patrol car doing paperwork, observed a man walking up behind him on the driver’s side and recognized that the man was Clemmons. Imagine how the officer felt exiting from the driver’s seat. He was close to becoming another victim when he ordered Clemmons to stop and show his hands. Clemmons did not show his hands and began to run away in the other direction, going around the vehicle.

Again telling Clemmons to stop, the officer drew his gun. Clemmons seemed to be reaching for a gun. Kelly fired shots. At least two rounds stopped Clemmons, who had already been shot in the torso two days before during a struggle with one of the officers slain in Parkland. At the time of his death, Clemmons was armed with a .40-caliber pistol taken from one of the Lakewood police officers at the scene of the massacre.

Kelly was justified in using deadly force to stop Clemmons because he had reason to believe Clemmons had already committed the violent murders of four officers. Thus, even if Clemmons had not presented an imminent threat to Kelly, Clemmons would have posed an imminent threat to the public if he got away.

Clemmons was an individual who wrestled with his own private demons. Society extended compassion toward Clemmons when he convinced an Arkansas parole board and Gov. Mike Huckabee that he was a changed man.

Many mistakes are bound to occur in a compassionate and open society like ours. The watchmen at the walls may let down their guards.

Nevertheless, in one sense, you and I are no different than the officers that walk the thin blue line. You and I need to exercise situational awareness. Whether you are sitting in your car, relaxing in a restaurant or walking in the park with your family — stay on guard.

The best safety equipment we have is an alert mind. Take your gun, but don’t leave vigilance behind.