SOCIAL MEDIA POSTS – CAN THEY BE USED AGAINST A DEFENDANT AT TRIAL?

On December 19, 2025, the U.S. Court of Appeals for the Ninth Circuit issued its decision in United States v. Justus, No. 24-1641, affirming the conviction of Robert Alvin Justus, Jr. for his role in a shocking ambush that killed one federal security officer and wounded another during protests in Oakland, California.

The Court Explained:

At trial, the government presented 73 exhibits from Justus's social media activity to support its theory that Justus and Carrillo pre-planned the attack as part of their anti-government ideology. On appeal, Justus argued that the district court erred in admitting this evidence because it was irrelevant, constituted improper character evidence, and was highly prejudicial. The panel rejected these arguments. The district court did not abuse its discretion in finding Justus's social media posts and communications relevant to the crime charged and admissible under Fed. R. Evid. 401.

The district court did not abuse its discretion in finding that the evidence was not impermissible character evidence under Fed. R. Evid. 404(a), as it was admitted for a non-propensity purpose: to demonstrate Justus's state of mind at the time of the attack. The district court properly reviewed Justus's posts before deciding whether the probative value outweighed the danger of undue prejudice and did not abuse its discretion in admitting the social media evidence under Fed. R. Evid. 403.

The panel held that the district court did not err in instructing the jury that duress is not a defense, where Justus agreed that a duress defense was unavailable and the district court granted the government's request to bar Justus's invocation of duress as an affirmative defense. The district court, which allowed defense counsel to admit duress-like evidence to establish Justus's mental state, appropriately provided an instruction to help guide the jury on the parameters for which it could consider duress-like evidence.

Background: A Drive-By Shooting Amid 2020 Protests

The case stems from events on May 29, 2020, during widespread protests in Oakland following the murder of George Floyd. Justus drove a van past the Ronald V. Dellums Federal Building, where two Protective Security Officers (employed by the Federal Protective Service) were stationed outside providing security.

From the passenger side, Justus's co-defendant, Steven Carrillo—an active-duty U.S. Air Force sergeant at the time—opened fire with an assault rifle. The attack killed one officer and seriously injured the other. Carrillo, linked to anti-government "boogaloo" extremist ideology, later killed a Santa Cruz County sheriff's deputy in a separate incident.
Justus pleaded not guilty and was convicted after trial on charges including murder of a federal officer and attempted murder. He appealed to the Ninth Circuit, challenging aspects of his conviction and possibly his sentence.
The Ninth Circuit's Ruling

In a published opinion, the three-judge panel upheld Justus's conviction in its entirety. According to the court's summary:

Justus acted as the getaway driver, enabling Carrillo to carry out the premeditated attack.
Evidence sufficiently proved Justus's knowing participation and intent, rejecting any claims that he was unaware of the plan or merely present.

The court found no reversible errors in the district court's evidentiary rulings, jury instructions, or other trial procedures raised on appeal.

The panel affirmed the judgment of the district court, meaning Justus's conviction stands. (Sentencing details were not highlighted in the summary, suggesting the primary appeal focused on guilt-phase issues.)

Social Media Evidence: Admissibility of Posts and Online Activity

A key issue on appeal involved the admission of dozens of Justus's personal social media posts at trial. Prosecutors introduced these posts—showing his interest in violence, anti-government sentiments, and ties to the "Boogaloo Bois" movement—to demonstrate motive, intent, and premeditation. Justus argued that the evidence was irrelevant, constituted improper character evidence under Federal Rule of Evidence 404(b), and was unduly prejudicial under Rule 403.

The Ninth Circuit rejected these challenges, finding that the district court did not abuse its discretion in admitting the posts. The evidence was deemed directly relevant to proving Justus's shared ideology with Carrillo and his voluntary participation in the attack, rather than mere bad character. This ruling aligns with broader federal practices where social media content is
routinely admitted if properly authenticated and relevant.

In general, social media posts and "readings" (e.g., likes, shares, or viewed content) can be admitted in federal trials if they meet evidentiary standards:

Authentication (FRE 901): Courts require a prima facie showing that the evidence is what it claims to be. For posts, this often involves circumstantial evidence like account ownership, distinctive content, or witness testimony linking the defendant to the account. Screenshots alone may suffice if supported by context.

Relevance (FRE 401): Posts showing motive, intent, or planning (as here) are highly relevant in criminal cases.

Hearsay and Exceptions: Defendant's own posts are typically non-hearsay admissions (FRE 801(d)(2)).

Character Evidence (FRE 404): Posts can be admitted for non-character purposes, such as proving knowledge or absence of mistake.

Prejudice vs. Probative Value (FRE 403): Courts balance potential unfair prejudice against evidentiary value, often favoring admission in cases involving ideology-driven crimes.

In extremism cases like this, social media has proven crucial for establishing affiliations and mindset. The Justus decision reinforces that online expressions of violent or anti-government views are fair game when tied to the charged conduct.

Broader Context

This case highlights the intersection of domestic extremism and violence against law
enforcement during the turbulent summer of 2020. Carrillo received a life sentence for his broader spree, which authorities tied to far-right "boogaloo" motives aiming to incite civil unrest.
Justus's affirmed conviction underscores the Ninth Circuit's stance that accomplices in targeted attacks on federal personnel face severe accountability under laws protecting officers.

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