Appeals court upholds conviction in South Carolina ‘white powder’ letter case
A federal appeals court upheld the conviction of a South Carolina man who prosecutors say devised a scheme to weaponize law enforcement and a state licensing board against his estranged wife during a divorce, culminating in anonymous threatening letters stuffed with white powder sent to police.
In a decision issued Monday, the U.S. Court of Appeals for the Fourth Circuit upheld the conviction of Jonhathan McCaslan, who in 2024 was found guilty by a jury of cyberstalking, mailing a threatening communication and two counts of making a false chemical threat under a federal anti-hoax law commonly associated with anthrax-era scares.
A small town feud, escalated
The case unfolded in Calhoun Falls, S.C., a town so small that one witness described it in court as “small town South Cackalacky,” and where, according to the appellate opinion, there were essentially two places to eat: a grill and a 7-Eleven.
Prosecutors portrayed McCaslan as determined to gain leverage in divorce proceedings with his wife, Kimberly, by repeatedly drawing police scrutiny toward her — including tipping off an officer that she would be at a restaurant and allegedly driving on a suspended license.
The escalation, however, went far beyond that.
An inquiry from the state nursing board, which sought information about Kimberly’s prior legal trouble, was sent not to her, but to an email account belonging to McCaslan, according to the opinion. The nursing board later received a mailed letter that appeared to be a confession from Kimberly, claiming misconduct serious enough to jeopardize her nursing career.
The letters and the powder
Then came what the appeals court called the turning point: two threatening letters involving a white powdery substance.
One, delivered to the home of Officer Jordan Smith, of the Calhoun Falls Police Department, on Rice Street, included a typed message warning him he “cannot hide behind that badge,” alongside powder that immediately alarmed Smith and his fiancée.
Initial field-testing suggested the possible presence of fentanyl, prompting a response that ultimately involved the South Carolina Law Enforcement Division’s bomb squad, which later determined the substance was harmless. Laboratory analysis identified ingredients consistent with milk-based infant formula, water, and linseed oil, the opinion said.
A second letter — also containing white powder — was intercepted before reaching a police post office box, and appeared directed at another officer with the department.
The legal fight: Is ‘powder in an envelope’ a chemical hoax?
On appeal, McCaslan argued that the evidence was insufficient for the false chemical threat convictions because the letters did not explicitly mention chemical agents or weapons. A powdery substance alone, he said, should not satisfy the federal hoax statute.
The court rejected that argument, emphasizing that the statute focuses on the defendant’s conduct and the circumstances, not specific words in the text of a letter.
A jury could reasonably conclude, the panel said, that including white powder in hostile mail was meant to convey the false impression of a dangerous chemical substance — and that recipients could reasonably believe an “attack” might be underway, especially given the emergency response that followed.
DNA evidence survives chain-of-custody challenge
McCaslan also attacked the handling of evidence, arguing the government could not reliably authenticate items used for DNA testing because of gaps in the chain of custody — a challenge complicated by the death of a local officer who initially collected the evidence and could not testify at trial.
But the appeals court said the government did not need a “perfect” chain, and that other testimony, video evidence, and documentation were sufficient for a jury to find the items authentic. Crucially, forensic testing found McCaslan’s DNA on the stamps affixed to the Rice Street letter, which served as a key piece of evidence tying him to the mailing.
A conviction affirmed and a reminder of the post-anthrax legal era
The ruling leaves intact a federal jury’s conclusion that what began as a bitter martial dispute became something else: a case about how easily panic can be manufactured with an envelope, a printer and a spoonful of powder.
Even when the substance is harmless, the court noted, hoaxes can trigger costly emergency responses and divert law enforcement from real threats — precisely what Congress sought to deter when it strengthened federal anti-hoax laws after the early-2000s anthrax scares.
McCaslan’s conviction was affirmed. He was sentenced to five years probation on each of the four counts to run concurrently, and is not currently incarcerated, according to court records.
