When Does Self-Defense Apply in Assault Cases?
April 28, 2025
When someone is charged with assault, they may feel like the legal system is already stacked against them. But the law recognizes that not every violent act is a criminal one.
Sometimes, people are forced to protect themselves or others from harm. That's where the legal principle of self-defense comes into play.
Understanding when self-defense applies can be the difference between freedom and a conviction in a criminal defense case.
Bretz Legal, LLC, a law firm based in St. Louis, Missouri, offers valuable insights into what qualifies as self-defense in assault cases, how Missouri law approaches it, and what someone accused of assault needs to know.
Assault Charges in Missouri
Before diving into self-defense, it's important to understand what assault means in Missouri. Assault can range from threatening someone with physical harm to actually causing serious injury. Missouri law divides assault into four degrees, with first-degree assault being the most serious.
Missouri's Degrees of Assault Include:
First-degree assault: Attempting to kill or knowingly cause serious physical injury.
Second-degree assault: Causing injury with a deadly weapon or due to recklessness.
Third-degree assault: Knowingly causing physical injury to another person.
Fourth-degree assault: A broad category that includes threats, offensive physical contact, or attempts to injure.
Each level carries different penalties, ranging from fines and probation to years in prison. The severity of the charge often influences how self-defense claims are viewed in court.
What Missouri Law Says About Self-Defense
Missouri is considered a "stand your ground" state, which means there's no duty to retreat before using force if you're in a place where you have a legal right to be. The law supports the idea that people shouldn't have to back down when they're threatened, as long as the force they use is reasonable under the circumstances.
According to Missouri Law, Self-Defense May Apply If:
The person reasonably believed that force was necessary to protect themselves from harm.
The level of force used matched the level of the threat.
The person wasn’t the initial aggressor (with some exceptions).
These rules apply to both physical force and deadly force, though the bar is higher when someone uses deadly force. In those cases, the threat must involve serious physical injury or death.
Conditions That Must Be Met for a Self-Defense Claim
Self-defense isn’t automatically accepted by the court. Several conditions have to be met for it to be considered a valid criminal defense.
For Self-Defense to Hold up in Court, the Following Must Be True:
There was an imminent threat: The danger had to be immediate, not something that might happen later.
The threat was unlawful: The person claiming self-defense couldn’t be responding to a lawful action, like an arrest.
The response was proportional: Deadly force can't be used in response to a slap or shove.
The person had a right to be there: They weren't trespassing or committing a crime at the time.
Courts often look closely at these factors. If any of them are missing, the self-defense claim may not succeed.
Key Differences Between Physical Force and Deadly Force
In Missouri, the law separates the use of regular physical force from deadly force. This distinction plays a big role in how self-defense claims are evaluated.
Self-Defense Involving Physical Force is More Likely to Apply When:
The person is being pushed, grabbed, or struck.
The threat doesn’t involve a weapon or life-threatening behavior.
The response stops once the threat ends.
Deadly Force is Only Justifiable If:
The person genuinely believes they’re at risk of death or serious injury.
It’s used to stop a violent felony like robbery or rape.
There was no safe way to avoid the threat.
Using deadly force carries much more legal risk. Courts require strong evidence that it was the only reasonable option.
How the "Initial Aggressor" Rule Affects Self-Defense
Missouri law generally says you can’t claim self-defense if you started the fight. But like most legal rules, there are exceptions.
Someone May Still Claim Self-Defense if They Were the Initial Aggressor But:
They tried to withdraw from the confrontation.
The other person continued the fight despite that effort.
In criminal defense law, this rule exists to prevent people from starting fights and then trying to claim they were just defending themselves. But it does leave room for someone who acted impulsively and then tried to walk away.
Reasonableness in Self-Defense
A big part of any self-defense claim is whether the person's belief that they were in danger was reasonable. This is a legal standard based on what an average person would think in the same situation.
Factors Courts Consider When Judging Reasonableness Include:
The history between the people involved.
The size and strength of each person.
Whether weapons were present.
The behavior of the alleged victim (e.g., making threats or acting violently).
Even if the person claiming self-defense was mistaken, they might still have a valid defense if their belief was reasonable under the circumstances.
Transitioning From Accusation to Defense Strategy
Once someone is charged with assault, the process of defending themselves legally begins. Self-defense can be a powerful tool, but it requires more than just saying, "I was protecting myself." Building a solid defense takes a detailed understanding of the law and the facts of the case.
That’s where working with a criminal defense attorney becomes critical. An attorney can analyze the incident, identify whether self-defense applies, and present evidence in a way that meets Missouri's legal requirements. Reach out to Attorney Bretz for support.
Evidence That Supports a Self-Defense Claim
When raising a self-defense claim, evidence is everything. Without solid proof, the court might not believe the story, even if it's true.
Common Types of Evidence in Self-Defense Cases Include:
Witness testimony: Statements from people who saw the event unfold.
Medical reports: Showing injuries consistent with a defensive response.
Surveillance footage: Capturing the incident as it happened.
911 calls or texts: Proving fear or intent to seek help.
Photos of injuries or the scene: Providing visual context.
The more details an attorney can gather, the stronger the defense will be.
How Missouri's Stand-Your-Ground Law Applies
Missouri’s stand your ground law allows people to use force without retreating, as long as they’re somewhere they have the right to be. This law has been a major part of self-defense cases and often becomes a central issue in court.
Under The Stand Your Ground Law, Someone May Use Force If:
They aren’t the aggressor.
They reasonably believe force is needed to prevent harm.
They aren’t committing a crime at the time.
The law gives people stronger legal footing when defending themselves, but it doesn’t mean anything goes. The force still has to match the threat.
Transitional Thoughts on Legal Support
Even with Missouri's favorable self-defense laws, assault charges are serious. Prosecutors often challenge self-defense claims aggressively, especially when someone is badly injured or weapons are involved. The legal process can be long and stressful, but with the right approach, a strong defense is possible.
That makes it all the more important to work with a lawyer who understands how St. Louis courts handle these cases. Knowing local judges, prosecutors, and jury expectations can make a real difference.
What to Do If You're Accused of Assault but Acted in Self-Defense
If you’ve been accused of assault and believe you acted in self-defense, the steps you take early on can shape the entire case.
Here’s What to Do Right Away:
Stay silent: Don’t try to explain your side to the police without a lawyer present.
Gather evidence: Keep any texts, photos, or witness contacts.
Write down your memory of the event: Details can fade quickly.
Contact a criminal defense lawyer: The sooner, the better.
A calm, focused approach gives you the greatest shot at building a successful defense.
Reach Out Today
Self-defense is a legal right, but it's also a strategy that has to meet certain conditions to work. If you or someone you know is facing assault charges and believes self-defense played a role, it's crucial to speak with an experienced criminal defense attorney. Bretz Legal, LLC serves clients in St. Louis, Missouri, and the surrounding areas of St. Charles County, Jefferson County, Franklin County, and St. Louis County. Call now to schedule a consultation.