In a split second, law enforcement officers must recognize a threat, evaluate its seriousness, and instantaneously employ potentially deadly force against criminal suspects to combat apparent dangers to citizens, bystanders, fellow officers, and themselves. Because they must make decisions in a split second, officers can be reasonably expected to maximize their own safety by taking pre-emptive action, however, because officers are trained to think quickly in light of the facts and circumstances confronting them and to respond quickly, rationally and effectively they should not be relieved of their responsibility to reason and respond rationally.
Pre-emptive action (taking action once a threat has been recognized, but before the threat can be carried out) is authorized under the law.
The law also absolves the officer of liability if he/she makes a mistake when taking pre-emptive action “if a reasonable officer could have believed the conduct at issue was lawful, in light of clearly established law and information the officer involved possessed.”

However, before an officer may legally use deadly force as a pre-emptive action to stop what he/she perceives to be a threat to his/her safety, the perception, that he/she is being presented with a threat of serious bodily harm or death, must be a reasonable perception.

The reasonableness of the officer’s threat perception and the reasonableness of the response is analyzed by asking the “objective reasonableness” questions set out by the U.S. Supreme Court in 1989. (1) would other reasonable officers on the date of the incident, considering the same facts and circumstances, have perceived the threat the same way; and (2) would other reasonable officers, on the date of the incident, have responded in the same manner.

Much of the argument for the need for officers to take pre-emptive action is based upon the concept known in the law enforcement profession as the “reactionary gap.” Where did this concept called the “reactionary gap” come from?

In 1983, Salt Lake City, Utah Police Lieutenant Dennis Tueller wrote an article titled How Close is Too Close? Tueller reported in his article that “it takes an average officer 1.5 to 1.7 seconds to recognize a threat, draw his sidearm and fire two rounds at center mass but an average suspect charging at the officer with a knife can cover a distance of 21 feet in less than 1.5 seconds.”

That means that an officer attacked without warning by a suspect with a knife is likely to be stabbed if the suspect was within 21 feet of him when he started his attack.

The explanation for the 1.5 to 1.7 second delay in a police officers response to a spontaneous attack was given the acronym PEDA because the officer has to Perceive the threat, Evaluate the threat, Decide on what action to take in response to the threat, and then Act on the threat. This concept has become known in the law enforcement profession as the “reactionary gap” and has been used in officer safety training since 1983. Some officers have erroneously interpreted Tueller’s research to mean that a suspect’s action will always beat an officer’s reaction.

However, two factors were important in Tueller’s findings that have been lost in the application of his findings over the past 30 years. First, Tueller was only talking about spontaneous attacks. In other words, the officer has been surprised by the attack.

It has almost become “gospel” in the law enforcement profession since Tueller’s article was published that “action always beats reaction.”

However, we tested whether action beats reaction when the attack is not spontaneous. We did that by timing how long it takes a person carrying a firearm in his hand extended by his side to raise the weapon and fire at an officer and we timed how long it takes an officer, who already has his weapon aimed at a potential threat, to recognize the threat taking place and respond by firing his weapon. In other words, an officer’s response to the actions of a suspect when not surprised and ready to use deadly force if necessary. Here is what we found.

In conducting the first stage of our experiment we use a shot timer, similar to those used in competition shooting. Upon activating the timer it randomly sounds a buzzer as an indicator to begin the exercise. In this scenario an armed subject was holding a pistol in his right hand, down at his side. A responding police officer was approximately 20 feet away using a patrol car as partial cover. The officer is armed with a patrol rifle equipped with a holographic site and is aiming at the subject. Once the buzzer sounds the armed subject attempts to fire a shot at the police officer. Upon detecting movement the officer fires a shot at the subject.

The second stage of our experiment utilized the shot timer to determine the time it takes for an armed subject to raise their pistol and fire a shot at the police officer. In this scenario, when the buzzer sounds the subject raises the weapon and taps it’s muzzle on the shot timer to simulate firing a round.

Our experiment was conducted a number of times and consistently found the officer could respond, to the subject’s action of raising their firearm, in approximately .26 seconds, while it took the subject approximately .48 seconds to raise and fire theirs.

In conclusion, as law enforcement officers we cannot see into the future or read the mind of an armed subject. However, the purpose of this experiment is to demonstrate that officers who are prepared to use deadly force against an armed subject do not have to use their weapon preemptively based solely on the fact a person is holding a firearm in a non-threatening manner. Our desire is we can minimize the number of allegations of excessive force by officers in these type of cases by training them action does not always beat reaction in a non-spontaneous attack.