Tomasz Kosowski

Tomasz Roman Kosowski was born in Poland on January 8, 1979, and later moved to the United States with his family.

He grew up in New Mexico and developed an early interest in music and science. At the University of New Mexico, he studied music, with a focus on classical guitar, while also completing studies in biochemistry. He later earned a master's degree in biomedical sciences.

Kosowski attended Dartmouth College, where he earned both a medical degree and an MBA. He subsequently completed training in plastic and reconstructive surgery, including fellowships in New York, Atlanta and Miami.

In 2016, Kosowski joined the Laufer Institute of Plastic Surgery in Dunedin, Florida. He became known professionally as a plastic surgeon specialising in cosmetic and reconstructive procedures, including breast surgery.

Kosowski eventually left the practice and established his own medical business. His professional relationship with his former employers would later become the foundation of the civil litigation that prosecutors identified as the background to Steven Cozzi's murder.

Kosowski was convicted of murdering one victim, attorney Steven Cozzi.

In 2019, Kosowski filed a civil lawsuit against his former employer, the Laufer Institute of Plastic Surgery, and several former colleagues. He claimed that problems involving medical billing had damaged his income and professional reputation.

Steven Cozzi, an attorney with Blanchard Law in Largo, represented defendants in the lawsuit. As the litigation continued, Kosowski eventually began representing himself after his own lawyer withdrew.

The dispute became increasingly contentious. Kosowski filed repeated motions and sought Cozzi's removal from the case. Prosecutors later argued that his hostility toward Cozzi had become personal and eventually developed into an obsession.

On March 21, 2023, Cozzi arrived at the Blanchard Law office. At approximately 9:50 a.m., he went into the men's restroom and never returned.

His wallet, keys and cellphone remained at the office, as did his vehicle. Investigators discovered a significant quantity of blood in the bathroom.

Surveillance footage showed a man entering the building earlier that morning and later leaving while pulling a large cart containing a covered object. Investigators identified the man as Kosowski. The cart was taken to a gray Toyota Tundra associated with him.

Kosowski subsequently returned to his Tarpon Springs home. Later that day, he drove a red Toyota Corolla south toward Collier County. Investigators tracked the vehicle through license-plate and traffic-camera records.

Cozzi's body has never been found.

Police arrested Kosowski on March 25, 2023, and charged him with first-degree murder.

The investigation uncovered extensive evidence that prosecutors said demonstrated preparation for the killing. Among the evidence were blood and DNA findings, surveillance footage, digital searches concerning Cozzi, searches relating to license-plate devices, and searches for the paralysing drug succinylcholine shortly before Cozzi disappeared.

Prosecutors alleged that Kosowski killed Cozzi inside the law firm's bathroom, transported his body from the building in the cart and later disposed of the remains in a dumpster. The remains were ultimately believed to have entered the waste system and been taken to a landfill.

Kosowski's convicted offense involved a highly planned attack against a specific individual with whom he had been involved in a prolonged civil dispute.

According to the prosecution's evidence, Kosowski conducted surveillance and research concerning Cozzi before the murder. Investigators identified searches for Cozzi's home and personal information, as well as searches concerning license-plate concealment and the effects and dosage of succinylcholine.

On the morning of March 21, 2023, prosecutors said Kosowski arrived at Cozzi's workplace carrying equipment and supplies. His cellphone was switched off before he reached the law office and was later switched back on around the time of his participation in a scheduled telephone court hearing.

Surveillance footage showed him leaving the building with a large cart. Prosecutors argued that Cozzi's body was inside the cart.

The prosecution also presented evidence concerning the Toyota Tundra, a license-plate switching device, cleaning materials, protective equipment and other items recovered during the investigation.

The body was never recovered, making the case dependent on the cumulative forensic, surveillance, digital and circumstantial evidence presented at trial.

Kosowski was arrested on March 25, 2023, four days after Cozzi disappeared.

Investigators had traced his movements from the Blanchard Law office to his Tarpon Springs home and then south toward the area of Collier County.

At the time of his arrest, investigators reported finding a substantial amount of cash, firearms, protective equipment, masks, duct tape and a vial containing succinylcholine.

Kosowski remained in custody while the case proceeded through a lengthy series of pre-trial proceedings.

Kosowski's murder trial began in September 2026, more than three years after Cozzi's disappearance.

Before trial, Kosowski dismissed his attorneys and chose to represent himself. He also waived his right to a jury, leaving Judge Joseph Bulone to determine both guilt and, if necessary, the sentence.

The prosecution presented surveillance footage, blood and DNA evidence, cellphone and vehicle-location data, internet-search records and evidence concerning the equipment allegedly used to transport and dispose of Cozzi's body.

The prosecution argued that Kosowski had deliberately planned the killing as a consequence of his dispute with Cozzi and the defendants represented by Cozzi.

Kosowski disputed the prosecution's reconstruction of events. In his closing argument, he argued that the State's theory was physically impossible and challenged whether prosecutors had proved that Cozzi was dead without recovering his body.

On September 23, 2026, Judge Bulone found Kosowski guilty of first-degree murder.

During the penalty phase, the judge found two aggravating circumstances proven beyond a reasonable doubt: that the murder was committed for financial gain and that it was cold, calculated and premeditated without legal or moral justification.

The judge rejected the State's allegation that the murder was especially heinous, atrocious or cruel, finding that the absence of Cozzi's body meant the precise manner of death had not been established sufficiently to prove that aggravator.

Kosowski has not yet been sentenced. A Spencer hearing is scheduled for October 8, 2026. He faces either life imprisonment without the possibility of parole or the death penalty.