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Cover and time: Limitations and hazards

As de-escalation continues its momentum in public discourse and LE curricula, all must remember that the concepts of cover and time apply differently when guns are in the mix

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When situations are potentially dangerous, law enforcement officers (LEOs) are trained to use cover when feasible. Shielding is advisable when facing weapons of all types, including personal weapons (fists, knees, etc.), and knives or clubs.

In non-firearm scenarios, closing a door or putting a vehicle or another obstacle between the assailant and the officer can hinder and delay an assailant’s imminent attack. In non-firearm scenarios, use of shielding or blockades gives officers more time to talk to the person and more time to try other non-deadly techniques to resolve the situation. For many years this has been a mainstay among de-escalation techniques used by LEOs facing people armed with knives and clubs.

In cases of an incoming assault with a knife, LEOs cannot hesitate to respond with force sufficient to quickly overcome the level of resistance they face. Because of the propensity for law enforcement’s non-deadly weapons to fail, especially against fearless assailants, often the risks are too high to respond with something other than deadly force.

The timing advantages gained by using blockades versus subjects with knives and clubs, along with the associated principles of cover, are not the same when LEOs face assailants with firearms. Officers have tried to apply the same strategies (cover, time, and/or talk), only to be shot in their covered positions. As de-escalation continues its momentum in public discourse and in law enforcement curricula, all must remember that the concepts of cover and time apply differently when guns are in the mix. Here are some things to consider.

Cover is a weapon barrier. Cover provides physical protection. At an incident involving a suspect with a firearm, cover offers some protection against incoming bullets. We appreciate and exploit the life-saving potential of cover. Nevertheless, because deadly resistance and the timing thereof are the assailant’s choice, officer-involved shootings often occur when officers are at close range in the open with no cover available.

Concealment is a vision barrier. Concealment might block assailants from seeing potential victims or responders. It might block LEOs from seeing a hiding suspect or from seeing a suspect’s weapon.

Some objects that block vision don’t provide any protection from bullets. A residential interior door may provide concealment, but it provides no bullet cover. Bullet-resistant glass may provide cover, but no concealment. For most weapons faced by American LEOs, a solid, thick, concrete wall provides concealment and cover. That is said with caveats.

Cover is always fallible. Cover is relative, tenuous and partial. Cover is defeated by shoot-throughs, bypasses, ricochets and maneuvers.

Cover is relative. Whether an object is actually cover depends on the type of weapons and munitions used by opponents. For instance, a ballistic blanket is cover from typical handgun bullets; it is not cover from center-fire rifle bullets.

A shoot-through is a bullet that penetrates the object being used as concealment or cover. Facing an adversary armed with a center-fire rifle, shoot-throughs will occur on a ballistic blanket. The same is true of typical body armor worn by LEOs – rifles easily shoot through it.

Body armor is not cover. A typical ballistic vest only protects the officer from common handgun bullets that strike a protective panel. A vest helps, so we wear it, but patrol vests give virtually no protection in many other scenarios, including rifle fire, dagger attacks and angles. A vest-wearing officer’s heart is exposed to any bullets entering from either side. (More on bypasses later.) Rifle plates front and back offer no protection from the sides, either.

Through the shoulder, under the armpit, directly into the side, there is a high risk of mortal wounds from side angles, as well as from upward and downward angles. When the officer is in the living room, for instance, an assailant in a bedroom directly above can shoot through the floor, with the bullet entering the officer’s unprotected body at a downward angle. During the rapid dynamics of lethal fights, an officer’s sides are exposed at various moments to virtually all angles. Furthermore, and to state the obvious, vests provide no protection for the lower abdomen and pelvis, legs, femoral arteries, arms, and no protection for the officer’s head and neck.

Cover is tenuous. Cover doesn’t last. Cover is easily defeated by the opponent’s maneuver – changing their position (angle of fire) relative to the location and position of the officer’s cover.


Left: the officer appears fairly well covered; however, shoot-throughs, bypasses, and ricochet hits are possible. Right: at this distance, when the assailant maneuvers one step to the right (as demonstrated by this camera angle) the officer’s vitals are completely exposed to direct fire.

Also, when enough bullets are shot into a piece of cover (like a tree or a brick wall), shoot-throughs eventually become possible, making that piece of cover temporary.

Cover is partial. Even when a person is completely covered from one direction, at the same time they are exposed to different angles. While covered to the known threat, officers are usually exposed to unknown threats behind them and to their sides.

LEOs often use cover as part of their containment around a potentially dangerous person who is barricaded or hiding. The principle of containment requires officers to maintain constant observation of the suspect’s site or structure. Otherwise, the suspect could simply slip away undetected, making the supposed containment a useless gesture. When an LEO looks over or around cover to maintain observation of a suspect’s location, an assailant within that area can target the LEO’s head.

This creates a dangerous paradox:

  • If I cannot see the suspect or their egress locations (doorways, windows, etc.), then the suspect can slip away and escape. Worse, they can maneuver, flank me and shoot me from an uncovered angle. So, I must be ever-watchful.
  • If I can see the suspect or into the place where they are hiding (assuming I don’t have something like a pole camera), then they can shoot me in the head.

This video below shows an officer using cover in the front yard of a house from which an assailant just shot at other officers. At the 0:55 mark you’ll see the officer using the principles of cover and containment, observing from behind a large tree with his rifle ready when the assailant inside the house shoots the covered officer outside:

A bypass is a bullet that misses someone’s cover and continues unobstructed. This happens through the sides when wearing patrol body armor. It also happens when part of the assailant’s body is exposed – LEOs can place a well-aimed shot at their assailant, bypassing the opponent’s cover to achieve a hit. Likewise, LEOs are sometimes struck by incoming rounds that bypass their own cover and hit an exposed part of the officer’s body.

A ricochet is a bullet that skips off a surface and continues at an angle different from its initial flight. Ricochet is another way people who are using cover get hit by incoming bullets. Off the hood or side of a police car, for instance, or off the pavement under the vehicle, rounds can glance off surfaces and continue. Officers peering around corners, over police car hoods, or standing on the pavement can be struck by ricochets while using cover.

Luck is a factor in every fight and tactical operation. Luck drifts both directions, for and against the good guys. Whether a hit is well-aimed or lucky is irrelevant. A hit is a hit. The officer or the assailant is injured to the same degree either way.


In this photograph, the officer’s lower legs are exposed to ricochets under the car even though we can’t see them for direct targeting. The officer’s head and neck are exposed to bypasses (direct fire), as well as ricochets off the hood and windshield.

The risks of unprotected angles, shoot-throughs, bypasses and ricochets, along with the suspect’s ever-present option to maneuver and entirely deprive the officer of cover, are hazards always present when LEOs face suspects armed with firearms, even when officers use cover.

Be that as it may, for emphasis I’ll restate that the risks of standing flat-footed in the open outweigh the risks of using cover; so, we use cover when we can. But we don’t train to stand flat-footed in the open any more than we train to sit still when a lethal attack springs upon us.

Using cover is a defensive strategy. Defense is good, but by itself, a defensive use of cover will not stop the oncoming attack. Training to run for cover first when under fire might be based on misplaced confidence. Especially in close quarters situations, when someone shoots at an LEO the LEO should immediately shoot back with rapid accuracy until the threat is suppressed.


Does using cover buy time?

My assailant has the same amount of time as me. We experience time at the same time. Time comes and goes at the same rate for both of us. In moments of conflict, what matters is what my assailant and I do during the time we face each other.

One hypothetical argument made in support of the cover-buys-time theory is that the assailant can shoot me now as I stand in the open, but if I jump behind cover he cannot shoot me right now. So, doesn’t that buy me time to survive?

Without also acting to stop the assailant, the answer to the survive-behind-cover question is maybe and only temporarily. The officer might get hit by a shoot-through “right now,” having under-estimated the assailant’s armament or ammunition, or overestimating the cover’s ability to stop bullets. As the officer peers around cover to keep track of the assailant, a bypass can hit the officer in the head right now. If the officer relinquishes visual observation – completely ducks behind cover – then yes, until cover is defeated by the assailant’s maneuver the officer’s use of cover may add some survival time. But the greater risk when looking away is that the assailant will maneuver unnoticed and, therefore, strike unopposed.

We’ve known these principles for many years in policing. When I went through the basic academy more than 30 years ago I was trained on lessons learned from the Newhall incident involving the California Highway Patrol in April 1970. While Officer Alleyn used the cover of a police car he was struck and killed by bypasses. While Officer Pence reloaded his weapon behind the cover of another police car, suspect Twinning maneuvered and killed Pence at close range. [1]

During a gunfight, if I need to apply a tourniquet to my leg or clear a stoppage in my pistol – if I need to do anything – it’s safer to do that behind cover than in the open. But that doesn’t mean I have extra time. It only means the object between me and my assailant might stop what he fires at me during the time that I apply a tourniquet or fix my gun. And that applies only as long as suspects remain where they are (assuming they don’t already have an angle of fire directly at me), and as long as I don’t get struck by a shoot-through, bypass, or ricochet.

Cover gives the illusion of gaining time if the assailant patiently waits for me to do what I want to do behind cover. In that case, it isn’t cover that buys me time. It is the assailant’s choice to wait that gives me a brief reprieve. Sad experience teaches LEOs that determined assailants often don’t politely wait; instead, they seize the initiative.

In a tactical setting, initiative is the freedom to act. Initiative is the ability to choose when and how to act or to not act. It is the ability to begin or continue with a plan or task. A tactical commander who has the initiative places the suspect in a reactionary mode and forces him to respond rather than act. Likewise, a suspect taking action puts LEOs in the position of reactionaries.

That is the point of Col. John Boyd’s doctrine on the OODA Loop. Within that cycle, on the conflict’s timeline the person who is acting is ahead of the person who is reacting. The person with the initiative has lead time. The reactor experiences lag time. That is why action beats reaction. That is the essence of the reactionary gap.

Timing favors the side that presently has the initiative. Thus, “an implied objective of every operation is to gain and maintain the initiative.” [2] Initiative works both ways, for the good guy or for the bad guy. Regardless of any purported time-slowing de-escalation strategies used by the police (such as time, distance, shielding, and talking), when the assailant seizes the initiative – when they act – timing is on their side.

Facing a knife or club, cover and distance sometimes give officers time and opportunity to talk to their adversary. In contrast, when we deal with a person who has access to a firearm we talk when the situation is not lethal, whether we are behind cover or in the open. We shoot when things become lethal, whether we are behind cover or standing in the open.

A high-risk traffic stop is illustrative:

  • We use cover and distance with our firearms ready as we talk suspects out of their vehicle and into custody. (For non-LE readers, you need to know that this technique works only when suspects choose to submit.)
  • LEOs recognize that their vehicle is vulnerable to shoot-throughs. The engine block and pillars stop bullets and other portions can, but incoming bullets can miss those shielding structures and continue. Officers also know their legs and heads are exposed to bypasses, ricochets and rounds skipped off the pavement under the car. Officers recognize that the assailant can deprive officers of all cover by maneuvering. A moving target is hard to hit; and if an assailant rushed the officers or ran to execute a flanking maneuver, partial cover would quickly become no cover.
  • When a suspect chooses lethal resistance with a gun, officers are necessarily trained to respond with accurate gunfire, even when they have their police vehicles as partial cover. If the assailant’s background isn’t immediately clear, then officers are trained to earn a clear shot by maneuvering.
  • When the subjects of a car stop – high risk or otherwise – escalate to firearm resistance, officers who talk (attempt de-escalation) instead of shoot get murdered or get lucky. This is true even when officers are rightfully using their cars as cover.

There are ways to maximize a vehicle as cover. Nevertheless, even when we get behind the engine block or stack pillars (position ourselves behind an alignment of two or more pillars), officers cannot wait for the notion of cover-bought time to win a gunfight for them.

Offense is one of the principles of all tactical operations, from large-scale operations to the one v. one gunfight in the street. As useful as defensive cover is, by itself defense does not stop an opposing assailant.

This video is illustrative. At about the 32-second mark you’ll see a gunfight between a Dallas police officer (wearing all dark uniform) and an armed assailant who ambushed police officers on July 7, 2016. The officer uses the pillar of a building as cover. The assailant uses maneuver and offense to defeat the officer’s cover.

Time favors the side taking decisive action. This principle is especially true when a situation becomes deadly, regardless of the acting person’s role (police or assailant), regardless of a person’s intentions (good or evil, with or without malice), regardless of their mental health or illness, and regardless of a chemically induced state of mind.

When an officer gets behind cover, if the officer doesn’t also act to stop the assailant – if the officer waits – then the initiative (timing) is up for grabs. If the assailant uses the officer’s wait time to maneuver into a different position where the assailant can target the officer, then the officer’s time behind cover favors the suspect.

Other examples challenge the statement that “cover buys us time” in gunfights.

  • If it takes an officer 3.0 seconds to perform a combat reload while standing in the open, when that officer gets behind cover can they perform the same reload in 1.5 seconds? Of course not.
  • If an assailant can fire one well-aimed bullet every second at an officer standing in the open, then when the officer crouches behind cover at the same distance does the assailant’s ability to fire well-aimed shots decrease to two-second splits? No. The assailant can still deliver the same shot group in one-second intervals, but those well-aimed bullets may now be blocked or deflected.

Buying time comes from doing things more efficiently. For example:

  • In skills testing three months ago, fictional Deputy Smith delivered five A-zone hits in 4.0 seconds at a distance of 5 yards. Not satisfied, Smith asked for and got help from department instructors. Smith practiced. Today at a distance of 5 yards Smith can deliver five A-zone hits in 2.5 seconds. Deputy Smith “bought” 1.5 seconds of advantageous timing.
  • Likewise, three months ago Smith performed a combat reload in 3.5 seconds. After several weeks of dedicated effort, Smith can now reload in 2.0 seconds. Deputy Smith “bought” an additional 1.5 seconds of gunfighter time.

The price of each purchase was personal practice.

Cover and timing


Critical hits are bullet wounds that cause incapacitation.

Cover stops or deflects bullets. That’s it. That is the conditional statement of truth. Conditional, because all cover is relative, tenuous and partial.

We are grateful for the principle of cover. Therefore, we look for cover and use it when it is available. However, using cover does not alter principles of timing, nor does it solve the problem at hand. Incapacitation stops the problem.

In a shootout, time usually favors the side that scores the first critical hits on their opponent. Critical hits are bullet wounds that cause incapacitation. We recognize that close-quarters combatants can shoot each other simultaneously. And, due to the delayed effects of most bullet wounds, opponents can hit each other sequentially before incapacitation occurs in the first. Be that as it may, the person who earns critical hits first usually wins. “First” is an important reference to timing.

Time doesn’t care who delivers those hits, who gets hit, or how it’s done. Time doesn’t care whether the hit was lucky or well-aimed, done in the open or when using cover. Time doesn’t care whether a hit was due to a bypass, shoot-through, or ricochet. The first critical hits principle has superiority over the use of cover principle.

The collective law enforcement experience in the United States demonstrates the tactical realities of these cover and timing principles. Newhall and Dallas weren’t anomalies. For instance:

  • Miami-Dade County, Florida, April 1986, two serial bank robbers engaged eight FBI agents who used their cars as cover in the shootout. Two agents were killed, five others were seriously wounded.
  • Deputy Kyle Dinkheller was killed in January 1998, Laurens County, Georgia. Dinkheller’s dash-cam video shows the assailant maneuver to deprive Dinkheller of the cover of the police car.
  • Officer Justin Hurst was murdered on his 34th birthday in March 2007. At the conclusion of a vehicle pursuit, Hurst remained in his police car as cover, including when the suspect began shooting. Hurst tried to increase distance (was backing up) when he was shot.
  • In April 2009, in Okaloosa County, Florida, two deputies located a domestic violence suspect in the parking lot of a shooting range. The suspect didn’t cooperate with the arrest. One deputy tased the man who, while downed by the influence of the TASER, drew a handgun and started shooting at the deputies, who ran for the cover of their nearby police vehicles and returned fire. The assailant maneuvered, changed his angles of fire, and both deputies were killed. The suspect led other deputies in a lengthy pursuit that ended in a dramatic crash, where the assailant was killed in another gun battle with several other LEOs.
  • In April 2011 in Conroe, Texas, a police sergeant used his car as cover while talking to a man holding a shotgun. The man shot the sergeant in the face. Other officers returned fire and killed the assailant.
  • In August 2012 in Oak Creek, Wisconsin, an active shooter at the Sikh temple engaged the first arriving officer in the parking lot. The officer ducked under a car for cover. The assailant maneuvered and shot the officer 15 times. The officer survived.

There are more examples, but these are sufficient to make the point.

When a suspect escalates to a firearm assault, because of the life-threatening reasons described in this article, LEOs are wisely and necessarily trained to get critical hits first, regardless of the availability of cover.

A version of this article was originally published in the spring 2020 edition of The Tactical Edge, the professional journal of the National Tactical Officer’s Association (NTOA).


1. See the video starting at 17:40 for Alleyn and starting at 20:45 for Pence.

2. Charles “Sid” Heal teaches these concepts on initiative in “Field Command,” pages 256 and 353.

Deputy Chief Kyle Sumpter has over 30 years of law enforcement service. He was a patrol officer, FTO, training coordinator, major crimes detective, firearms instructor, SWAT officer and team commander, and graduated from the FBINA session 237. Kyle was on two seasons of the reality shooting competition show Top Shot. He teaches deadly force, de-escalation and resolving lethal situations to law enforcement officers throughout the state of Washington. Reach him at