matt gutman. And want to play doctor? Reporter: A case crazy enough to be a movie, if the movie "Catch me if you can" with leonardo DiCaprio playing a chameleon con man, pretending to be, among many... See More
matt gutman. And want to play doctor? Reporter: A case crazy enough to be a movie, if the movie "Catch me if you can" with leonardo DiCaprio playing a chameleon con man, pretending to be, among many other things, a doctor. Dr. Harris? Yes. Do you concur, doctor? Reporter: The real story of a faker in a hospital happened at osceola regional medical center in kissimmee, florida. A teenager caught pretending to be a physician's assistant. Reporter: An imposter in the emergency room. August, 2011, matthew scheidt, a fresh-faced young man, reports for duty in the e.R., In scrubs, a stethoscope and a badge identifying him as a p.A., A physician assistant, as close as you can get to being a doctor without an md. Do you know if they're hiring here at the hospital? What do you want to do? I'm a doctor. Reporter: Like dicaprio in the movie, scheidt oozes confidence. He's kind of charming. He is charming. He is, he's very charming. Reporter: Unlike dicaprio's character, who gets queasy in the emergency room, scheidt is drawn to the action. He performed procedures on patients. Reporter: Reporter nancy alvarez, with channel 9 in orlando. This kid touched patients. This kid held a child who was getting stitches. He actually administered cpr. Yes, he actually administered cpr to one patient. Reporter: But apparently unsatisfied, scheidt demands more privileges. He kept on going back to human resources saying, I need the access, I need the access. And that's when they're, like, he's not even a physician assistant or a student. I appreciate you coming down, I absolutely do. Reporter: He talks his way from the emergency room into a police interrogation room. I don't sign off on anything. I just did the circling. Reporter: So confident he can talk his way out of anything, scheidt waives his right to a lawyer -- and begins to tell his tale. I told them it could be kidney stones could be kidney infection could be uti. He just was talking, talking, talking, and talking. I had an interest and still somewhat have an interest in the medical field. Reporter: An interest? Yes. A license -- no. In fact, scheidt had no education, medical or otherwise, beyond a diploma from an online high school. He is not a physician assistant. What he is, is a 17-year-old kid with a summer job at a doctor's office. I just did clerical work. I assisted one of the physicians I'm good friends with his daughter. Reporter: He used to run errands to the hospital, so he asked them for an i.D. Badge, and somehow got that one that let him prowl the e.R. For a total of nine days. IN THE MOVIE, DiCAPRIO'S Make-believe medical expertise comes from tv. Doctor, do you concur? Reporter: Nowadays, yep, there's an app for that. Scheidt's knowledge came from smart phone games. Like speed anatomy and stuff like that so I could learn the anatomy and stuff. Reporter: But the seriousness of his masquerade is soon apparent. One of the techs had to run out of the room to go get something and I was told to take over cpr by a physician. Reporter: There's no evidence it was his fault, but that elderly patient he did cpr on, she died the next day. Reporter nancy alvarez broke the news to the deceased woman's husband. When you told him that his wife had been under the care of matthew scheidt, what did he say? He was shocked. I think he felt betrayed more than anything. Reporter: Confronted by police, scheidt blames his charade on the hospital for handing him that incorrect i.D. Badge. Let's even says that I said i was a p.A., Are you that stupid that you're just going to put me in the system as that? Without any credentials or any paperwork or nothing? Reporter: The osceola medical center tells "20/20" -- "today at our hospital our badging process is significantly more secure." Then an eye-popping, jaw-dropping revelation. Scheidt unwittingly unmasks himself as a serial imposter. A "catch me if you can" career that began, authorities say, with scheidt posg as a nurse at another florida hospital, when he was just 13. I did that a long time ago like when I volunteered there i shadowed a doctor. The incident was handled internally. There was no report to law enforcement or anything like that. Reporter: As to why he does these things, scheidt drops hints -- it felt right, like I was supposed to be there and I was supposed to be learning by them. They were supposed to be teaching me. He wanted to learn, he wanted to do. But they always kind of had to hold him back a little bit because he was a kid. Reporter: The interrogation ends, scheidt is charged, and posts bail. But then, something inexplicable. He was picked up in miami, now as an imposter of a police officer? Police say scheidt is packing a badge, taser, and a loaded gun. Miami beach cops arrested him, pulled up next to him in a crown vic and told him to buckle his seat belt. Pulled up next to a real cop he confidence of a real cop, but he's just a kid pretending to be one. Reporter: Back in orlando august 2012. He goes on trial for practicing medicine without a license and impersonating a physician assistant. I was sitting just a few feet away from him and there were tears in his eyes and he looked petrified. And I felt for him for a moment, and then I wondered, hmm. Could this be real? Because -- could he be performing again? We the jury find the defendant guilty on -- Reporter: Convicted on four felony charges, he would serve a year in jail. Do you think that the punishment did not fit the crime? People seem to forget that this is a 17-year-old child that did these acts. And now you have a 17-year-old kid who made some immature decisions who has had to do time and get a conviction on his record as a felon, and he's going to have to deal with that for the rest of his life. Reporter: Whatever the rest of his life hold, he will likely never be a real fission assistant and certainly not a real police officer. Even so, some suspect his career as a professional copy cat might not be over. Do you think that this is the last time that you will report about matthew scheidt? I'm gonna tell you something, I'm not convinced that this is the very last time we'll see matthew scheidt in the news or in our court system.
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