Missouri Court Affirms Convictions Based on Surveillance Video and Accomplice Liability
A recent decision from the Missouri Court of Appeals illustrates how surveillance footage and circumstantial evidence can support serious criminal convictions—even when the State cannot identify every participant or prove that any property was actually taken.
In State v. Armstrong, No. ED113515 (Mo. App. E.D. Sept. 1, 2026), the Eastern District affirmed convictions for first-degree involuntary manslaughter, attempted first-degree robbery, and armed criminal action. The defendant received an aggregate sentence of 15 years in prison.
The decision is particularly important for Missouri criminal cases involving surveillance video, attempted offenses, and accomplice liability. It also demonstrates why defense counsel must make specific and timely objections at trial to preserve evidentiary issues for appeal.
What Happened in State v. Armstrong?
The charges arose from a fatal shooting at a Mobil gas station near Interstate 70 and Union Boulevard in St. Louis.
Earlier surveillance footage showed the defendant entering the driver's seat of a red Buick SUV. Real Time Crime Center cameras then tracked the SUV as it traveled toward the gas station.
According to the gas station's surveillance video, the SUV initially drove past the station, made a U-turn, circled the parking lot, and stopped near a truck where the victim was pumping gas. Two armed men approached the victim while a third person stood nearby. Following an altercation, one of the men shot the victim.
The individuals returned to the SUV, which left the area at high speed. The vehicle ran a red light and swerved through traffic as it traveled toward St. Louis County.
Although the gas station video did not show who was driving when the SUV left, the State introduced other evidence connecting the defendant to the vehicle. Cell phone records placed his phone near the gas station at the time of the shooting and along the SUV's route afterward.
The defendant testified that he had left the vehicle shortly before the shooting to use drugs. He could not explain who replaced him in the driver's seat and maintained that he did not remember how the substitution occurred. The jury rejected that account.
A General “Lack of Foundation” Objection Was Not Enough
The defendant first argued that the trial court should not have admitted the surveillance videos because the State failed to establish the necessary foundation.
At trial, however, defense counsel had made only a general “lack of foundation” objection. Counsel did not specifically explain whether the alleged problem concerned authentication, identification, relevance, accuracy, or some other element of the required foundation.
That distinction proved critical on appeal.
The Eastern District explained that an objection must be sufficiently specific to inform the trial judge what is allegedly missing. A specific objection also gives the State an opportunity to correct the problem by presenting additional testimony or evidence.
Because the defense did not identify the particular defect in the foundation, the appellate court held that the issue was not properly preserved. The defendant was therefore limited to requesting discretionary plain-error review, which requires a showing of an evident, obvious, and clear error resulting in manifest injustice or a miscarriage of justice.
The court declined to grant that review.
This is a significant lesson for any criminal case involving digital evidence. An attorney ordinarily cannot preserve an issue merely by saying “foundation” or “objection” without explaining the legal basis for excluding the evidence.
How Can Missouri Prosecutors Authenticate Surveillance Video?
Missouri courts traditionally permit a witness familiar with the subject matter of a video to testify that it fairly and accurately represents what the witness personally observed.
But many surveillance systems record events automatically. In those cases, there may be no witness who personally watched the event as it occurred.
Missouri courts have therefore recognized what is sometimes called the “silent witness” theory. Under this approach, a recording may be authenticated through evidence demonstrating that the recording system operated properly and that the resulting footage is reliable, even without an eyewitness who can verify every image.
In Armstrong, a detective testified that he located the gas station's cameras and recording equipment, examined the equipment, reviewed the recordings, and determined that the system was functioning properly. He also identified a discrepancy of approximately two hours in the displayed timestamp, downloaded the relevant footage, and concluded after reviewing it that the footage was accurate.
The Court of Appeals found that the videos were highly relevant and displayed strong indications of reliability. Even if the original foundation had been incomplete, the defendant did not show that the State would have been unable to supply the missing evidence if counsel had made a more specific objection.
Attempted Robbery Does Not Require Property to Be Taken
The defendant also argued that the State failed to prove an attempted robbery because nothing was taken from the victim.
That argument did not persuade the court.
To prove an attempt under Missouri law, the State must establish that the defendant acted with the purpose of committing the offense and took a “substantial step” toward completing it. A substantial step is conduct strongly corroborating the firmness of the person's criminal purpose.
The State's evidence included the SUV's movements before the shooting, its missing or damaged license plates, the positioning of the vehicle for an escape, the armed men approaching the victim from different directions, and the victim's vulnerable position while pumping gas. The participants then fled together immediately after the shooting.
The court concluded that a reasonable jury could find that the participants had taken substantial steps toward committing a robbery, even though the shooting interrupted the crime before they obtained any property.
Accomplice Liability Can Extend Beyond the Person Holding the Weapon
The defendant was not accused of being the shooter. Nevertheless, Missouri law does not require the State to prove that a defendant personally performed every act constituting an offense.
A person may be held criminally responsible when he acts with others and promotes, aids, or assists the commission of the crime. Participation may be inferred from the person's presence, conduct before and after the offense, association with the other participants, and flight from the scene.
The Court of Appeals concluded that the surveillance videos, cell phone evidence, circumstances surrounding the attempted robbery, and the defendant's role as the SUV's driver permitted the jury to find that he acted in concert with the armed participants.
The court also deferred to the jury's decision not to believe the defendant's explanation that he somehow exited the moving SUV during the few seconds it was outside the view of surveillance cameras. A factfinder may consider a defendant's false or implausible explanation when evaluating consciousness of guilt.
What Does This Decision Mean for Missouri Criminal Cases?
Armstrong does not establish that merely being present in a vehicle automatically makes someone responsible for every crime committed by its occupants. The State must still prove the elements of each charged offense beyond a reasonable doubt.
The decision does show, however, that prosecutors may establish participation through the combined force of circumstantial evidence. Surveillance footage, phone-location records, coordinated conduct, association with other participants, flight, and an implausible explanation may collectively support a conviction even when no single item of evidence proves the entire case.
For the defense, the case emphasizes the importance of investigating the reliability and completeness of video evidence, examining timestamp discrepancies, obtaining all available footage, testing cell phone evidence, and making precise objections at trial.
Speak With a Missouri Criminal Defense Attorney
Cases involving surveillance video and accomplice liability are highly fact-dependent. A person may face serious criminal exposure even when the State does not allege that the person fired a weapon or personally took property.
An experienced Missouri criminal defense attorney can evaluate whether the State can authenticate its digital evidence, whether the alleged conduct constitutes a substantial step toward a crime, and whether the evidence actually establishes purposeful assistance rather than mere presence or association.
