Patrick Morley
Vice President
McCarthy Byrnes

May 8, 2026

40 Use‑of‑Force Cases Every Law Enforcement Officer Should Know (6-10)

Core Use of Force & Qualified Immunity (Part 2)

Last week, I began sharing a series of 40 essential use‑of‑force cases that every law enforcement professional, from police, sheriff, corrections, probation, parole, and federal- should understand, be able to explain, and recognize in day‑to‑day operations.

Again, it is important to note that this series is not ranked or ordered by importance. Every case matters.

Additionally, as mentioned in the first article, while the focus is on United States Supreme Court decisions, officers must remember that state law, state constitutional provisions, and departmental policy may be more restrictive. Supreme Court rulings establish the constitutional floor, not the ceiling. Your state statutes, case law, and agency directives always control your daily practice. Law enforcement personnel should read these cases individually to gain a full understanding of the complex legal issues involved.

As we continue the series, today we move deeper into qualified immunity and use-of-force analysis, focusing on how courts evaluate officer decisions in fast-moving, uncertain, and legally evolving situations.

These cases emphasize a critical reality: the law does not require perfection from officers-it requires objective reasonableness under the circumstances. They also clarify how courts determine whether an officer should be held personally liable, particularly when the law is unclear or still developing.

Understanding these rulings helps officers recognize not just what the Constitution prohibits, but also how courts interpret split-second decisions in the field.

6. Mullenix v. Luna, 577 U.S. 7 (2015)

Fact Pattern: An officer positioned on an overpass fired at a fleeing suspect’s vehicle during a high-speed pursuit after the suspect, who was wanted on a warrant, threatened to shoot officers, and continued driving dangerously.

Rule: Qualified immunity applies unless existing precedent clearly establishes that the specific conduct is unlawful. Courts must not define “clearly established law” at a high level of generality.

Why It Matters: This case reinforces that officers are not required to find a prior case with identical facts. It protects reasonable decisions made in dangerous, rapidly evolving situations-even if, in hindsight, a different tactic might have been used. (It should be noted that some departments may have policies against shooting into occupied and moving vehicles that would restrict such an action.)

7. Brosseau v. Haugen, 543 U.S. 194 (2004)

Fact Pattern: An officer shot a fleeing suspect who was attempting to escape in a vehicle, fearing for the safety of nearby officers and civilians.

Rule: When the law governing a specific use of force is unsettled, qualified immunity protects the officer-even if the force may later be considered excessive.

Why It Matters: This case highlights how legal uncertainty benefits officers. If courts have not clearly defined the boundaries of force in a particular scenario, officers are unlikely to be held personally liable. It should be noted that in this case, the US Supreme Court did not make a ruling on whether the shooting violated the 4th amendment, rather holding the law was not clearly established, thus the officer did have qualified immunity.

8. County of Los Angeles v. Mendez, 581 U.S. 420 (2017)

Fact Pattern: Deputies entered a residence without a warrant and later used force during a confrontation. Police initially entered, having information that a potentially dangerous wanted parolee had been seen at that location. Lower courts held them liable under a “provocation rule,” (a rule, which makes an otherwise reasonable use of force unreasonable if the officer “intentionally or recklessly provokes a violent confrontation” and “the provocation is an independent Fourth Amendment violation. arguing their earlier actions created the need for force.)

Rule: Force must be judged at the moment it is used, not based on prior constitutional violations. The “provocation rule” is not a valid basis for liability.

Why It Matters: This decision narrows excessive force claims by rejecting the idea that earlier tactical mistakes automatically make later force unconstitutional. Officers are judged on the immediacy of the threat they face. Excessive‑force claims must be analyzed solely under Graham v. Connor, not by bootstrapping earlier Fourth Amendment violations into an excessive‑force theory.

9. Saucier v. Katz, 533 U.S. 194 (2001)

Fact Pattern: A protester alleged excessive force after being forcibly removed from a public event involving a government official.

Rule: Courts must apply a two-step analysis: 1) Did a constitutional violation occur and 2) Was the right clearly established at the time?

Why It Matters: This framework shaped how courts analyze force cases for years and remains foundational. It separates whether force was unlawful from whether the officer can be held liable.

10. Pearson v. Callahan, 555 U.S. 223 (2009)

Fact Pattern: Officers conducted a warrantless search under the “consent once removed” doctrine, which was later challenged as unconstitutional. (That rule, which had been adopted by lower courts permitted a warrantless police entry into a home when consent to enter has already been granted to an undercover officer who has observed contraband in plain view.)

Rule: Courts are not required to follow the rigid two-step sequence from Saucier. Judges may grant qualified immunity without deciding whether a constitutional violation occurred. The court concluded that the officers were entitled to qualified immunity because they could reasonably have believed that the doctrine authorized their conduct.

Why It Matters: This case gives courts flexibility and has led to more cases being dismissed on qualified immunity grounds early in litigation, shaping modern civil rights defense strategy.

Parting Thoughts (Part 2)

These cases underscore a central theme in modern use-of-force law: the Constitution allows for reasonable mistakes in uncertain and dangerous situations.

Qualified immunity is not a blanket shield-but it is a powerful protection when:

• The law is unclear
• The situation is rapidly evolving
• The officer’s actions are objectively reasonable under the circumstances

At the same time, these decisions show how courts carefully separate:

• Tactical errors vs. constitutional violations
• Bad outcomes vs. unreasonable force
• Clearly established law vs. evolving legal standards

For officers and supervisors, the takeaway is straightforward: You are judged based on what you knew and faced in the moment—not with hindsight.

@McCarthy Byrnes will present more cases to follow as we continue building a working, practical understanding of the law that governs use of force in the field.

We will examine:

• When force is reasonable
• When deadly force is justified
• How courts evaluate officer decisions
• How agencies must train and supervise
• When municipalities face civil liability