Joseph Gerard Cancellare was taken into custody Nov. 13 and faces one count of aggravated battery with a deadly weapon and one count of culpable negligence exposing another person to harm, a probable cause affidavit states. He was taken to HCA Florida Westside Hospital for medical clearance before being booked into the Broward Sheriff's Office main jail.

The incident dates to Aug. 14, 2025, when the woman returned home from work and found a blue envelope in her driveway. The envelope looked greasy and bore unfamiliar handwriting, and it was addressed to her using an address tied to a previous residence, according to arrest documents.

Inside was a greeting card with a brown substance spread across the interior. The woman recognized it immediately as peanut butter, dropped the envelope, called for help and ran inside to wash her hands. She told investigators she developed hives on both arms and a tingling sensation that lasted about six hours.

Her allergy is well documented. A prior police report from May 2017 recorded the condition, and investigators reviewed medical records detailing its severity. The woman said that even touching peanuts or encountering airborne peanut particles could trigger a dangerous reaction affecting her breathing and that, without immediate medical intervention, exposure could be fatal.

Police say Cancellare knew the woman personally and understood the risk. The two had known each other for more than 20 years and spent time together with their spouses in social settings, and witnesses said he had seen her take precautions when dining out or attending gatherings. The affidavit indicates the alleged motive involved a contentious divorce between Cancellare and his wife; the woman is a longtime acquaintance, not his spouse. Investigators also said Cancellare had made remarks to friends expressing a desire to harm people connected to the situation.

How investigators traced the envelope

Plantation police enlisted a U.S. postal inspector, who helped trace two Forever stamps on the envelope to a self-service kiosk at the Davie Post Office on South University Drive. A 15-digit code printed on the stamps identified the machine and the transaction that produced them.

The stamps were bought Aug. 8, 2025, with a Visa card, and the kiosk photographed the buyer. Police said the card belonged to Cancellare, and the stamps moved through a Miami postal facility on Aug. 13, the day before the envelope was found.

When shown the kiosk photograph, the woman immediately identified Cancellare, according to the affidavit. Several other people who knew him also identified him, including an acquaintance who had played in a band with him.

Police further alleged that Cancellare drove to a post office in a different city from where he lived, wore sunglasses inside in an apparent attempt to conceal his identity, and used a fictitious name and return address on the envelope. Detectives concluded he mailed the card knowing it could cause serious injury or death, and that he intended to cause death or serious bodily injury.

The investigation continued into 2026 as detectives gathered witness statements and medical records. Plantation police contacted Cancellare at his home on Nov. 13 and arrested him.

The case highlights the dangers faced by people with severe food allergies, for whom exposure to even trace amounts of an allergen can escalate quickly and require emergency care. It also underscores how postal transaction records and surveillance images can help investigators trace anonymous mail.