48 Hours - A Deadly Obsession: The Murder Trial of Dr. Kosowski

A missing lawyer, a plastic surgeon representing himself at trial, and a case filled with chilling details, including a murder bag and a paralyzing agent. "48 Hours" correspondent Erin Moriarty and "48 Hours" consultant Herman Weisberg unpack the murder trial of Dr. Tomasz Kosowski and the evidence that led to his conviction for the murder of attorney Steven Cozzi.

Duration: 34m
Broadcast on: 02 Oct 2026
Audio Format: other

I would say that the criminal act that the state accuses me of perpetuating is physically impossible. It is physically impossible to transfer a body in the manner the state suggests. Take into account what they're proposing. You take that full weight there, 200 pounds, and then a big and bulky cart. You take that. You lift it up straight in front of you and you get it on to that truck. That's physically impossible. I mean, maybe not for like an Olympic caliber deadlifter. And Mr. Bonderheit knows this very, very well. And that is why to refuse to lift up that cart yesterday. That was former Florida plastic surgeon, Dr. Tomas Kosalski, representing himself in court after being charged with the murder of 41 year old attorney, Stephen Causey. Despite his arguments and he made some good ones during his six day trial, Dr. Kosalski age 47 was found guilty of first degree murder on September 23rd. The doctor who now faces the possibility of the death sentence not only represented himself in court, but he waved his right to a jury. So instead asking for a bench trial. So he's leaving her up to a single judge alone to decide his fate, whether he'll live or whether he'll die. To understand how this case came about, you do need some history. The two men met because of a legal conflict. Dr. Kosalski had sued his former employer, the law for Institute of plastic surgery, and some of the people associated with the institute over a negative online review and a medical billing dispute. Stephen Causey just happened to be the lawyer for the defendants for the other side. But things apparently got so heated between the two men that in January of 2023 during a deposition, Kosalski confronted Kosalski in his law office's bathroom, calling him a scumbag. And that matters because it was in that same bathroom three months later that authorities believe that Dr. Kosalski came back in and killed Stephen Kosse. He was then arrested a few days later in a traffic stop with $280,000 in cash, brass knuckles, a paralyzing agent of medication, and a ballistic vest that was stained with Kosse's blood. Here's the important part for this case, Kosse's body has never been found. I'm 48 hours correspondent Aaron Moriarty, and this is case by case. Returning to the show today is 48 hours consultant Herman Weisberg. Herman is a private investigator, former NYPD detective, and he's also the managing director of Sage Intelligence Group, where he oversees investigations. Thank you, Herman, for being back with case by case today. Thanks for having me, Aaron. I really am honored to be working with you. I'm a big fan. And yes, this is a heck of a case. Herman, I first have to ask you your impressions of Dr. Kosalski in court. You have seen individuals represent themselves. I think he's a little different. He's incredibly educated. He seems sometimes even smug. I mean, do you think he was really prepared for what he did defending himself in a death penalty case? No, not at all. He was, to me, I was transfixed watching this. He looked like a deer in the headlights half the time. I don't know what he was thinking representing himself. The old expression comes to mind, you know, full for a client. But I would seriously rather see a lawyer perform surgery on himself than to watch this surgeon practice law or what he thought was practicing law. He didn't do himself any justice, literally. Well, what troubled me while I keep calling this troubling case is that there are a lot of people in this country who dislike lawyers, but this seemed to go beyond that. This was an obsession for this plastic surgeon, but there did seem to be some warning signs. As you know, Kasey's husband, Michael Montgomery, had actually feared for Kasey safety. He bought Kasey pepper spray and he testified that he fixed their home security system. And I think it was a smart move because a week before Kasey disappeared, Kosalski was found out of business near his law office and he was hiding an electrical closet with a torch lighter and a wagon, what's called a gorilla wagon, identical to the one that investigators believe he later used to transport Kasey's body. So it seems like everyone should have known that Kosalski was a threat. Was it, you think it's just that people didn't realize how far he would go for the husband to react by improving their security system and getting the mace and taking those steps? I really do

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