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

Episode Date: October 2, 2026

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.

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, that 200 pounds, in 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. Bonda Heid knows this very, very well. And that is why he refused to lift up that cart yesterday. That was former Florida plastic surgeon, Dr. Tomaz Kassowski, representing himself in court after being charged with the murder of 41-year-old attorney, Stephen Kossi. Despite his arguments and he made some good ones during a six-day trial, Dr. Casalski, 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 waived his right to a jury. So instead, asking for a bench trial.

So he's leaving it 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. Casalski had sued his former employer, the Lawford Institute of Plastic Surgery, and some of the people associated with the Institute, over a negative online review and a medical billing dispute. Stephen Kassi 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, Kuzowski confronted Kossi 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. Kaczywski came back in and killed Steve in Kazi. 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 Kasi's blood. Here's the important part for this case. Kasi's body has never been found. I'm 48-houre correspondent, Aaron Moriarty, and this is case-by-case. 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'm really 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. Casalski 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? 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, a fool 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, why I keep calling this a 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, Kazi's husband, Michael Montgomery, had actually feared for Kazi safety. He bought Kazi pepper spray and he testified that he fixed their home security system. And I think it was a smart move because a week before, Kazi disappeared. Kossowski was found out of business near his law office and he was hiding an electrical closet with a torchlighter and a wagon, what's called a guerrilla wagon, identical to the one that investigators believe he later used to transport Kasi's body. So it seems like everyone should have known that Kassowski 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 think that Kazi was concerned about it, but not to this extent. Have you ever seen grudges play out quite like this in all your years? years as a detective? Not like this one. You know, this, this, I think this doctor, they often, you know, you've heard the expression God complex.

I think he was not used to losing at all or ever being wrong. And this got to him and then he got fixated on it. This is a man that clearly snapped. I've seen a lot of litigation get out of control. I've seen really messy divorces. I've seen business breakups. Grudges get held. and the lawyer sometimes take the brunt of it, but not to this extent.

This is really one really bizarre and extreme case to me. It definitely seems like that. What kind of sticks out, though, about Katsalski is that he had no criminal history, right? I mean, why risk all of this? I think something really big was going on. And the disadvantage here is that he represented. himself. He didn't have an attorney to step in and make those evaluations for him. I have to say, you know, what's really important in this case is the fact that it's a no-body case.

Doesn't the fact that you have nobody, you don't have a cause of death, you don't have a weapon, make the circumstantial evidence in this case that much more significant, right? What they know is that Stephen Kazi disappeared, literally, disappeared from his office on March 21st, 2023. He went to the bathroom. He left an email unwritten, left his phone behind. But then he's never seen again. Can you talk about some of the evidence that then led investigators to look at Dr. Kozowski? Well, as we all know, the first 48 hours are extremely crucial in these cases. And I think the police did an appropriate job here. They definitely pounced on this. and they got right into preservation and collection of evidence in the video, which is kind of unusual.

These no body cases, they usually take a long time. It starts out as a missing person. And then it proceeds to be a homicide investigation. In this case, I think they were looking right away as possible abduction and or an assault or a homicide. Well, yeah, because I think Kazowski made an error by being. found a week before. You believe then that this, that the circumstantial evidence is very powerful in this case. Very, very powerful. You know, the stalking, the confrontation. And, you know, Kazi went back and obviously told his husband that he was concerned about this. So you've got that. You've got, you know, probably a limited amount of people that were looking to harm Kazi. You know, he's an attorney doing civil work, civil litigation. This is.

This is not somebody that's going around making enemies as far as I'm concerned, or as far as I know. 1022 that morning surveillance video outside that law office shows someone who really appears to be Kazowski, wheeling out a heavy wagon and then struggling to put it in a truck. It doesn't take a Sherlock Holmes level investigator to figure out something's happened and that he's either been abducted or murdered. Right. I mean, it was clear that Kazowski was going to be a suspect. I still find it shocking that he was. kidnapped in broad daylight, basically, in the morning, in his office, when he goes to the bathroom, prosecutors still had to convince the trier of fact, who happens to be a judge in this case,

how he got into the law firm and got Kazi out without anyone seeing him and how he did it on his own. At the top of this episode, we did hear Kaczyowski in court asking the assistant state attorney Nathan Vanderhide to do a demonstration. And I think he was trying to prove that he himself was not strong enough to have maneuvered the cart himself with a body on it. The judge did ultimately deny that request for a demonstration. But I did think that Kassowski made a point that it is what the state is saying he did does seem like it would be difficult. Difficult but not impossible in my view. I think the prosecutor avoided a trap there because the way Kuzowski described it,

it was basically picking up with your two arms, a 200-pound block. And anybody that's ever struggled with a too large a box or too heavy a box outside of a Home Depot or a television store knows that there's ways to maneuver boxes and carts into a car with a little bit of leverage. You get up underneath it. You lean it against the car. There are ways to do that. But this prosecutor was smart enough. the judge didn't allow it in the way it was presented by Kassowski to have him try to pick up something that would have definitely thrown the prosecutors back at. I know it would do it to mind.

There was a lot of other circumstantial evidence against Kassowski, including these flock cameras that showed that the truck that you see on video returned to Kassowski's home in Tarpon Springs on that very night that Kazi disappeared. And then four days later, Dr. Kozowski was pulled over. He was driving a different vehicle at Toyota Corolla, and the cops had a search warrant, so they had clearly been focusing on him. And inside his car, which I kind of mentioned,

but investigators found what they call a murder bag in this car with some really creepy contents. Can you talk about that a little bit? This reminds me of like an old, you know, cop show or detective show in the 70s. I'd probably turn the channel if I saw somebody carrying a bag like this. But they found cash, $280,000, which is an unusual amount of money for anyone to be carrying, unless you're planning on going away. They found brass knuckles, a paralyzing agent, a ballistic vest, which had Kazi's blood on it.

A ton of incriminating items. A Guy Fawks mask in the bag, you know, those scary masks that you've seen in the movies. One of the police officers noted that he was playing the Beatles song Free as a Bird on his car play as he was being arrested. And detectives found blood in the law firm's bathroom, the truck, Kazowski's car, his garage floor. They also found Kazowski. This is important. His U.S. and Polish passports were in the car. So this was really, you know, an investigator's dream.

It was like if an investigator got to write the script on this, what he would be looking for in a car of somebody that, you know, that was suspected of doing a crime like this. There's something else that I found really interesting about that arrest. There is a video. And he is in the back of the squad car. You actually see at first his hands are behind his back. But then he does this really strange move so that he's. he can bring his hands in front. And then he starts like, I don't know how else to put it. He's like sucking on his fingernails, almost gnawing on his fingers. What did you think was going on

with this? I have seen a lot of people been able to put handcuffs, rear cuffed people being able to put them in front of them. It's not easy at all. It takes a lot, a lot of effort. So he was really, really insisted on getting his hands and his fingers in his mouth. This could be read as a last stitch effort to get rid of some of the evidence. He knows that there's either blood or skin cells under his nails. That's my theory. If somebody has an alternative theory that they want to put in the comments, I'd be interested in hearing it because I don't think that's a nervous tick or that he was biting his nails or anything like that. You're going through a really a lot of effort. And I'd have to think that the doctor thought that there was some evidence on his on his fingers.

I have to agree with you. That's how I read it. This case also. contains some very strange, disturbing details that we have kind of alluded to. As you know, investigators found that paralyzing agent in Kaczyowski's car of medication and that they found that Kuzowski had researched how long the medication lasts. I assume you have a feeling of why, you know, we don't have the body. We don't know if he used it against Kazi, but why do you think he would have? have that with him. Well, the paralytic that they found in the syringe is called succinctocoline. It's a muscle relaxant, often used as an anesthetic during surgical procedure. So it makes sense

that Kazowski would have access to it and have knowledge of it. I'm surprised he had to look up the, you know, what the effects were. And we know it can be lethal at the right dose. It can be used so a victim can't fight back, but is still aware of what's happening to them. So that's, that's horrifying. You know, you're basically in a paralytic state. That's what the prosecution argued anyway. Has that ever come up in any cases that you've handled in the past? Not this specific drug, but I have seen, I've had a lot of experience with cases with knockout drugs, rohypnol or roofies. And, you know, I was lucky enough to be involved in a 48 hours episode about an attempted murder cheesecake case that was.

a drug called fanazepam. I mean, I think that when I read that, that was one of the most cruel details. The idea that a person, I mean, if in fact, and he was convicted, he didn't just want to inflict pain on him. He wanted Stephen Kasi to know it was happening and not be able to fight back. I can't think of anything worse than that. Now, as we've already mentioned, there is no body in this case. They've not been able to find Stephen Kossi. But there was blood.

There were traces of blood found at Kaczyowski's home and in his vehicles. The prosecution at trial called a blood pattern expert to the stand. Why would that be important in this case? So I've been involved in murder cases and I've seen what known as in the police department anyways, blood spatter experts. They reconstruct crime scenes. It's an art and a science as far as I'm concerned. But they can show, it's used often in blunt trauma, assault and murder cases, stabbing cases and other situations like that because they can recreate or reconstruct the crime scene.

And you can see, they can illustrate what position a victim was in, where the attacker was, which hand he was using. So it's fascinating to watch these people work. And I've seen it before at crime scenes. it's necessary in a case like this because you don't, like you mentioned before, Aaron, you don't have a cause of death. You don't have a weapon. And the crime scene is basically what you're working with here to prove your case. Well, yeah.

So you've got this problem. The prosecution has this problem that they have no body, but they believe that Kaczyzzi disposed of Stephen Kossi's body at a dumpster in Collier County, Florida. Again, this was just circumstantial evidence to support it, but they had George Volante, who was the garbage truck driver, who emptied this dumpster on March 23, 23rd, 23, two days after Stephen Kossi disappeared. And here's a recap of what he went through, and it comes from the prosecution's closing argument. I think George Volante's testimony, and I'm sorry that the Kossi's, and I'm sorry that Michael had to hear this, but the way he described it was fuzzle, that the odor was so bad, it's consistent with decomposition, the way it falls.

I mean, how important is this type of evidence, which is smell evidence? I think it's good evidence when you have somebody who's around garbage all day with all due respect. This man, you know, is an experienced garbage truck driver. He's used to smells, and he's used to smells that, you know, that resonate with him. And I really do think when you get a witness like this, it would have had a big impact on a jury. But I'm sure it got to the judge too. A judge understands that a guy who's surrounded by foul-smelling stuff all day, if something sticks out to him, that's definitely something that you want to introduce his evidence. You know, there's also a canine that were trained to detect human remains alerted to this dumpster.

I watched, they're called cadaver dogs. I watched them during the recovery efforts at the trade center. Amazing. I mean, there's rescue dogs that find living people, and then there's cadaver dogs, and they pick up a scent, and they don't give up. It's incredible. They can pick up that scent reportedly years later. So it's pretty interesting.

As Volanti testified, the dumpster had already been emptied and compacted. They were able to trace the contents of, you know, to a landfew. fill in Collier County, and they searched for three days, but they still couldn't find anybody. So they were able to prove Kazowski's guilt because his phone data was traced to that dumpster, and that's really, really important. There's no way to explain why you happen to be at a dumpster and all of these other circumstances. Again, I use the term exclusive opportunity here. His license plate was also captured in that area, which even just really nails in a coffin there.

Despite this overwhelming evidence, circumstantial evidence, albeit against him, Kazowski chose to represent himself in court and he decided he did not want a jury. He just wanted a judge. And that part really surprises me because at least with a jury, and he had to be thinking at this, you have a chance that one person will have reasonable doubt. That's what it seemed like, Kazowski was going for. and one person out of 12 might. So that was odd.

And it also was odd to me that even though he is representing himself, he didn't put on much of a defense. He didn't call any witnesses to the stand. I just want to play some of what the judge said, confirming this as Kaczyowski rested his case. I'm not going to call any witnesses. Right. Are you not going to call any witnesses?

You're not going to present any evidence and you're not going to testify yourself, correct? No, I presented evidence already in the case. Well on cross-examination, did you? What are you talking about? The transcript? No, the defense exhibit one. There was a photograph.

The other one to circulate you. All right? All right, but you're not going to introduce any further evidence, right? That's correct. Okay. So basically you rest, okay. Okay, Herm, I'm going to agree with you.

I mean, he really didn't know what he was doing. But it also struck me when I watch him because I hate this, that the defendant gets so much play at trial, not the victim. But I couldn't take my eyes off, Kuzowski. He seemed so emotionless. I mean, he's facing the death penalty. It was almost as you watched him that, I mean, there was a smugness to his face, too, like he was playing a game. But I think it's important to

note that Kazowski didn't start off representing himself. He did have attorneys at one point, and they filed motions on his behalf to fight the death penalty. And then afterwards, Kazowski withdrew those. And most important, I think, to you, is that Kasowski also refused to comply with a psychological evaluation. I would have loved to have seen that that psych evaluation. Even on TV and watching this, knowing what I know now, he had those,

I call him shark eyes, you know, just like that weird, distant look in his eyes like this, something, something, there's definitely obviously something off there, but it really stood out to me

when I watched, you know, the few times that the camera really, really focused in on him. this was I've never seen anything like this before. I have to agree, I have not either. I do think some of the more compelling moments

are when Dr. Kaczylsky tried to physically demonstrate his points because he's trying to raise reasonable doubt. You know, as you know, at the top of the episode, we have that clip of Dr. Kassowski in his closing statement, recounting his attempt to have the chief medical examiner. who was testifying to get into a cart so that the prosecutor would have to lift it onto a nearby table with a man in the cart.

The judge rejected that. And then later, Casalski asked the exact same medical examiner to get physically into a black trash bag. The judge denied that as well. You know, I thought he made a point, but do you think these demonstrations? demonstrations would have helped the case. I was a little surprised that the prosecution didn't offer testimony from something called a

kinesiologist. That's somebody who studies the human body movements and they understand how muscles and nerves and bones work together to do physical activity. If he had a lawyer, he could have introduced demonstrations. That's not the proper way to do that. You can't just haphazardly instruct people that are testifying to do, you know, a hundred push-ups or anything like that either. It's just the judge, I think, and I'm not an attorney, was correct in not allowing that.

But if Kazowski had proper legal advice or a legal counsel, they may have been able to introduce something to prove or disprove that a human would have been capable of doing that. It's just he didn't representing yourself. That's one of the pitfalls here. He just didn't properly do that. And the prosecution could have had their own experts to do that. It would have never worked in any court of law the way this man was trying to do it. Let's talk a little bit about the defendant. I hate putting the emphasis on the defendant.

But what's surprising about this case, honestly, is that Kaczylsky is a very educated man. Obviously, not in the law, but he has several advanced degrees, including he got his medical degree from Dartmouth. And whether he decided to represent himself came because he was arrogant or, otherwise, I don't think we'll really know or maybe he just was giving up. But before this happened, he had a lot of friends. They said he was known as Dr. Tampa Bay when he worked at the Lawford Institute of Plastic Surgery in Clearwater. And this whole thing started because he was defending his reputation. So it just seems so hard to understand how he could, end up in this situation.

And it really, some of it's explained in the complaint where Kazi and him were first introduced in the litigation that was going on. And I want to read the quote there because it's interesting to me. It was, it is important to really understand how negative reviews and negative allegations can have a huge impact on a career. It goes on to say, quote, in this day and age, a positive online reputation is key in securing medical services as everybody first Googles practitioners from which they will be getting medical services from end quote so the doctor was probably fixated on reading reviews about himself

again i have to bring in that god complex type of situation that you've heard so many times associated with some surgeons but his civil suit was an indication that he was going to get some pretty you know this is worse than any kind of negative review that you could probably try to get rid of on Google. This was going to be on the record here. So Kuzowski definitely, you know, he thought that this was the end of the world. And obviously it isn't said that this happened. But that's what I mean about somebody snapping. I almost think that's the only explanation. Because it's the part I don't understand. Why would anyone who clearly cared about his career and his image so much risk it all, throw it all away by.

killing the lawyer on the other side. It makes no sense. And again, I don't understand why he didn't want to argue his case to a jury. Because after he and the prosecution delivered their closing arguments, we have this one judge who's making a decision about whether guilt or innocence, and it only took that judge 15 minutes to reach a verdict. Here is the verdict. In the state of Florida, first Thomas Cossowski, case number 23,02935CF, the verdict. The court as a trier of fact, having considered testimony and evidence presented at trial, the exhibits emitted into evidence and the applicable law hereby enters the following verdict. The defendant is guilty of murder in the first degree as charged.

This verdict is rendered in open court this 23rd day of September, 2006, signed by Honorable Judge, Joseph A. Salone, circuit judge. All right. Thank you. All right. State, are you still seeking a sentence of death in this case? Yes, Your Honor. Herman, I know there was just one judge making this decision, but we are talking about a death penalty case. I mean, have you ever seen such a short period of time to deliberate for such a important sentence? Some of it makes sense that it was quick because, you know, the judges could take making contemporaneous notes while the evidence is being presented.

He doesn't have anyone to deliberate with. There's not one holdout juror that wants to ask some questions, which they're entitled to do and they should do. This is a judge that was probably sitting there saying to himself, the prosecution has given me enough that there's extremely convincing evidence here. And Kazowski didn't do himself any favors by not having a juror out there that may have said, oh, maybe you can't get somebody. into that box. Or maybe somebody couldn't get into that bag.

I had been surprised initially until I really looked at this case why it was a death penalty case. According to the state, they argued that Kazowski should be put to death, number one, because he committed this murder for financial reasons. But also because the act itself, which we have discussed during this podcast, was just so cold and calculated, because He said he's not going to fight the death penalty. And he's not planning on presenting any evidence to the judge to explain why he shouldn't be put to death. But I think to be safe, the judge did appoint special counsel who will argue to try to save Dr. Casalski's life. We will find out what happens when the judge decides life or death at the sentencing hearing.

on October 8th. Now, after that verdict was announced, Stephen Kasi's friends and family finally got to talk about him, and they delivered their victim impact statements, and I want to play some of these. I want to start first with Stephen's husband, Michael Montgomery. The most unbearable part is that we were never able to bring Stephen home. I cannot describe the horror this has brought me,

and all of steep loved ones, it brings me more anger than any than I can put in the words. It's always difficult to lose someone to murder, no question. But the no body cases, also it just, it leaves it open for family members. They have no one to bury. It doesn't feel like it's closed at all. Yeah, but you know, as investigators, we talk about all this work that goes into these no body cases, but it's really important to remember that the loved ones here have the real burden.

I can only hope that they were able to find closure maybe in the fact that this went the way it did as far as the court proceedings. And so sad for the spouse, you know, his husband seems like such a gentle, nice guy. And I felt for him. I have to agree. You get the impression that Stephen Kassi was a nice guy, was not one of these like cutthroat lawyers. So I can't imagine what his family is going through. I think it's also important to hear from Stephen's parents and what they said in court. You're going to hear first from his dad and then from his mother.

Steve was one of the warmest, kindest, friendliest, most genuine human beings you could ever hope to meet. He was vibrant and full of life. Every conversation with him left you smiling. His quick wit, his kind smile, and heartfelt transparency made him enjoy to be around. It would take me 41 years, 10 months, and 9 days to recount everything in my son Stephen's life that mattered to me. I cannot tell all of it today, but I can share what his loss has done to us. When the police told us they knew where Stevens remains were but could not recover anything,

our grief became something indescribable. We had no body to bury, no funeral, no rituals, no way to honor him in the way to honor him in the ways that families have honored, honored their dead for years? I think, I think this is a good reminder of how important these rituals are and how important it is for the victim's families to be able to say goodbye. So I hope this helped a bit. And I think it was very important for us, if we're going to talk about this case, that focus so much on the defendant, it's really important to end with how important the victim was,

Stephen Kasi. Thank you for letting me tell this story today, Herman. It's a very weird case, disturbing case, upsetting case. That's a rough one. And I feel the worst for the family, the families of Stephen Kossi. I appreciate you're having me on, Aaron. It's a tough case, and it's an interesting case, and I'm glad we're talking about it. And I really do hope this family you know, can find some closure. I hope so too. We'll be back next week with another episode of case by case. For our continuing coverage, you can check the case-by-case feed wherever you get your podcast.

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