Missouri Law on Assault with a Deadly Weapon
November 17, 2025
After an arrest for an alleged assault, you may face charges for assault with a deadly weapon. Perhaps you were defending yourself from a threat, or you were mistaken for the perpetrator. When you get the chance to make your phone call, use it to get Missouri assault legal defense.
Kirsch & Kirsch, LLC is a criminal defense law firm committed to protecting client rights and building strong defense strategies. Our proven track record in serious assault cases makes us the firm to call when you need a criminal defense lawyer in Jefferson City. In this blog post, we aim to provide information about assault with a deadly weapon as defined by Missouri laws and what you can do if you find yourself facing these charges.
Overview of Missouri Assault with a Deadly Weapon Laws
According to Missouri law, an assault with a deadly weapon charge is considered when it involves causing or intending to cause serious injury with a dangerous object, including firearms. These are serious charges that are most often applied as felonies.
A first-degree assault involves causing someone serious physical injury with a deadly weapon or having the intent to cause serious physical harm. Second-degree assaults usually involve causing physical injury with a deadly weapon or recklessly firing a gun. Third-degree assault is charged as a misdemeanor or felony, depending on the circumstances, which involve knowingly causing physical injury to someone else.
A separate felony charge may be applied as well. Known as Armed Criminal Action (ACA), this felony charge may be added to an assault conviction when a deadly weapon or dangerous object was used.
Possible Penalties and Consequences of a Conviction
Those who are convicted on charges of assault with a deadly weapon face some of the most serious penalties. An assault charge can be classified as a Class A, B, or C felony with prison sentences that range from 3 to 10 years for lesser classes. Class A felony charges may put you behind bars for 30 years to life.
If an Armed Criminal Action charge is also applied, a first-time offender could receive a mandatory minimum prison sentence of three years. During this sentence, parole, probation, or conditional release are not an option. If someone is convicted for assault with a deadly weapon a second time with an ACA charge, they will face anywhere from 5 to 30 years in prison on top of their underlying felony. No parole or probation is permitted in the first 5 years of the sentence. For third and subsequent offenses, there is a mandatory minimum 10-year prison sentence.
Beyond the prison sentences, there are other consequences of conviction on these charges that include:
Fines
When assault with a deadly weapon is charged as a felony, fines can be as much as $10,000 or more. The exact amount will depend on the severity of the assault charge.
Difficulty Finding Work
When you have a felony record, it will severely limit your job opportunities. Most employers conduct background checks, and when they see a conviction for serious charges like these, they will not hire you.
Losing Professional Licensure
Those whose professions require professional licenses, such as doctors, educators, attorneys, and law enforcement, can lose their credentials and be permanently barred from their profession.
Social Stigmas
Felony convictions often damage personal relationships. They can also complicate family matters, particularly if you share custody of your children with a former partner.
The Role of Intent in Defining the Crime
There is one key metric that defines assault charges that the prosecution must prove beyond a reasonable doubt. That element is intent, and the law requires that prosecutors show you had the intent to cause harm.
Whether the intent is to cause physical injury or instill deep-seated fear of injury, intent is the crucial factor here. However, be aware that recklessness doesn’t always excuse the behavior. In some cases, particularly when guns are the dangerous instrument in a second-degree assault, it may focus on your reckless behavior rather than specific intent.
Defense Strategies That May Be Employed for Defending Deadly Weapon Assault Cases in Missouri
While things may feel hopeless, your defense attorney will work with you and use evidence to create a strong defense strategy. Here are some of the ways these charges can be defended:
Self-Defense
Your lawyer may argue that the actions you took were necessary to protect yourself from imminent harm, especially if the force you used was directly proportional to the threat. Using reasonable force to protect another person or property from danger can also be a defense strategy.
Lack of Intent
Another way to challenge the prosecution is to prove that you did not intend to cause harm. If successful, the charges can be reduced or even dismissed.
Proportionate Force
Your attorney can also show that the force you used was proportionate to a threat you were facing at the time.
Insufficient Evidence
The prosecution may not have enough evidence to show beyond a reasonable doubt that the elements of this crime existed.
Unlawful Arrest
Defense attorneys can also look at the point in time you were arrested. If evidence reveals that this initial arrest was unlawful, you may see the charges dropped.
False Accusations
Some cases involve allegations that are either untrue or exaggerated. If you are in this situation, your defense lawyer will work to present evidence that shows this event either did not happen or was exaggerated.
Steps to Take If Accused of Assault with a Deadly Weapon
- Do not argue with the police: Doing so will almost always make things worse.
- Exercise your right to remain silent: Be polite when stating you wish to exercise your Fifth Amendment rights.
- Ask to speak to an attorney: When stating you wish to remain silent, let officers know you would like to speak to your lawyer.
- Contact an attorney immediately: Kirsch & Kirsch, LLC can help you by advising you on the best course of action, answering questions on your behalf, and preparing your defense strategy.
The Importance of Legal Representation from Kirsch & Kirsch, LLC
While your Constitutional rights also guarantee you an attorney provided by the state if you cannot afford to hire one, you should hire your own experienced defense attorney. Public defenders have huge case burdens, meaning that they are spread far too thin to devote proper time to a compelling defense strategy.
When you hire Kirsch & Kirsch, LLC, you get experienced criminal defense that helps you navigate the legal process and these complex charges while protecting your rights. Our attorneys work to mitigate penalties by challenging the evidence and negotiating plea agreements.
Understanding what you are facing is the first step, and our lawyers can explain the severity of this situation while working to protect your future and your freedom. If you have been arrested for assault with a deadly weapon, time is of the essence to start building your defense. Contact us today to discuss these criminal charges in complete confidentiality.
FAQs Regarding Assault Charges in Missouri
Are all assault charges felonies?
No, the degree assigned for the charge determines whether it will be classified as a felony or misdemeanor.
Can assault charges be dropped?
Yes, even these serious charges can be dropped, though it is not guaranteed. If the evidence is weak, it may be dismissed. Similarly, if self-defense can be proven or there were procedural errors made, things may work out in your favor.
How does Missouri law define a “deadly weapon”?
Missouri defines “deadly weapon” as any firearm, either loaded or unloaded. It also applies to any weapon that is specifically designed to cause serious injury or death, which includes daggers, knives, brass knuckles, and billy clubs.
What is a “dangerous instrument” under the law?
A dangerous instrument can be any object that, under the circumstances it is used, could capably cause serious physical injury or death. In other words, a dangerous instrument could be something as benign as a pen or a phone; the intent to use it to cause harm is what matters most.
What is Armed Criminal Action (ACA) in Missouri?
Armed Criminal Action is a completely separate and distinct charge from assault. It is often added in addition to other underlying felonies. This charge involves committing a felony using a dangerous instrument or deadly weapon and is characterized by requiring a mandatory minimum in consecutive prison sentences.
Do I need an attorney to represent me for assault with a deadly weapon charges?
You are entitled by law to have legal representation appointed for you by the state when facing criminal charges. However, it is best to hire your own Jefferson City assault lawyer. A public defender may not have previous experience representing other defendants with these types of charges. They are also burdened with many cases from the state, making it impossible for them to give each defendant their full attention.