Addicted To Love

A Plastic Surgeon's Risky Affair With A Patient Turns Deadly

(CBS)  Not so, according to Tennessee's chief state medical examiner, Dr. Bruce Levy. "When you see a series of injections in a nice straight line like that, you know it had to have been done to her," he says.

Dr. Levy feels quite strongly that the injections in her groin were made by an expert, like a doctor. "If you're off by as much as half an inch, it could be deadly," he explains.

And making it even more difficult for Lesa to inject herself, says Levy, is the fact that she was impaired by drugs at the time. "I think it was very clear evidence that Dr. Koulis was responsible for the injection. There’s just no other alternative that makes sense," Levy says.

To bolster that claim, Lesa's family points to a picture they say was taken just days before her death. "There was not a mark on her body. She was perfectly healthy. And there was not a sign of drug use in her behavior, her attitude one week long," Tara says.

Koulis and his attorneys believe he has no choice but to take the stand to defend himself. He tells the jury that he tried repeatedly to get Lesa to stop abusing drugs. "Lesa promised she’d stop. She'd go up and down. She'd stop and start. She'd stop and start," he claims in court.

When asked by his attorney why he didn't just leave Lesa, Koulis says, "Aside from the fact that I'm an idiot? Because I loved her and I wanted to be with her."

"And so to make her happy you looked the other way?" Roberts asks.

"I was unable to stop her one way or the other. She wanted to get high and she was going to get high. What precisely was I supposed to do? Tackle her?" Koulis replies.

Not buying his defense, the prosecutor confronts Koulis about his callous behavior that weekend. He acknowledges during cross-examination that though Lesa was high, and wasn't walking around or alert, he still had sex with her.

In fact, the doctor repeatedly had sex with Lesa even though she had complained of shoulder and chest pain that weekend, symptoms that Koulis concedes could have signaled a heart attack.

"Lesa had a very bad headache. She was complaining of shoulder pain and left arm pain. And she was having palpitations. Her heart was beating rapidly," Koulis says.

Koulis says he continued to have sex with her because, "She said everything went away. She felt fine."

In court, Koulis admits that he was primarily thinking of himself during that weekend.

And that may have not been the only time Koulis was just thinking about himself: prosecutors are about to introduce details of a previous incident, one in which Koulis has freely admitted injecting Lesa with addictive drugs.

Kim Helper points to an incident back in 2002 that was eerily similar. At the time, Lesa and Koulis were briefly living together in Kentucky.

"I was going through a very difficult time financially. Things were falling apart. And one day there was Demerol that was left over, and I had the really bad idea to try it. And I did. And I probably was instantly addicted to it," Koulis admits.

Koulis says he was shooting up frequently, and that he got the drug from his office.

And in the midst of his own downward spiral, Koulis admits he got Lisa addicted, too. "When she asked me for it, I gave it to her. I was impaired at the time," he says. "I realized, as did certain friends of mine, that this couldn't continue. That I was not myself. That I was not productive. And I realized that I needed help."