(CNN) -- Police raided a Las Vegas, Nevada, pharmaceutical supply store Tuesday as part of their investigation of Michael Jackson's death.
A pharmaceutical store in Las Vegas was searched Tuesday in connection with the death of Michael Jackson.
A source close to the investigation said it's believed that Jackson's personal physician, Dr. Conrad Murray, prescribed the drug propofol to Jackson within 24 hours of his death.
And two weeks ago, investigators searched Murray's home and office using a warrant that cited probable cause to believe the searches would uncover evidence of excessive prescribing, prescribing to an addict, or prescribing to or treating an addict, according to warrants given to CNN by Las Vegas affiliate KTNV.
Former prosecutor Paul Callan, who's also defended anesthesiologists in medical malpractice cases, sat down with John Roberts and Kiran Chetry on CNN's "American Morning" on Wednesday to talk about what could be going on with the Los Angeles Police Department's investigation.
The following is an edited version of the interview.
CNN: So, Paul, what do you make of the fact that they're out there yesterday, searching the supplied pharmacy services, and this comes the day after the LAPD said to the coroner's office, don't release the toxicology reports yet, we're still investigating?
Paul Callan: Well, I think it's very interesting, John, because there are also reports about Murray's personal life. Dr. Murray had severe financial problems, there are reports that he was deeply in debt. So obviously the focus now is getting tighter on Murray and they're looking to these pharmaceutical supply places to show that Murray was getting drugs, deadly drugs, prescribing those to Michael Jackson, and that those prescriptions may have caused his death.
CNN: [Jackson] died six weeks ago, and Dr. Murray is still the prime focus of the investigation, according to sources, but the fact that it's gone on for six weeks and they haven't charged him, what does that say about the case? You would think that, and I could be wrong about this, but you would think if they had an airtight case, they would've charged him by now.
Callan: Well, I'm not surprised. When you're trying to charge a doctor with manslaughter, a form of murder, it's a very, very severe uphill battle. You've got to show that the doctor acted with gross recklessness. Obviously nobody is going to be claiming here that Murray deliberately killed Jackson, as you would see in an intentional murder case. You have to prove gross recklessness in the prescription of drugs. That's really hard with a doctor because doctors are always prescribing drugs; patients occasionally die from them, that's not criminal conduct. But here, you have to show that this doctor should've known Jackson was an addict and that he could've died from these drugs.
CNN: You've defended anesthesiologists before. Have any of them ever been involved in a criminal case?
Callan: I've never seen a case involving criminal conduct. You know, it's interesting. I've represented three anesthesiologists this week in cases involving propofol.
Callan: Defended them at depositions. But it's routinely used. It's used during colonoscopies ...
CNN: It's one of those malpractice cases?
Callan: They're malpractice cases. They're cases where something goes wrong during the procedure and somebody dies. No one would even think about bringing a case against an anesthesiologist where an accident occurs in the operating room. But you see here, the claim is that Murray was hired at great expense and cost to the Jackson estate to prescribe drugs to him, and that Murray should've known that these drugs would kill Jackson.
CNN: Does he have an out here in terms of defending himself because propofol is not a controlled substance?
Callan: I don't think that will help him, ultimately. You have to remember, a drug being listed as a controlled substance just means that the federal government monitors dispensing of the drug a lot more carefully. But here, in terms of proving gross recklessness, even a non-controlled substance could be used in a grossly reckless way leading to criminal conduct. A little bit harder, but it can be done.
CNN: What about the pharmacy? If he was coming in and saying, "here are my prescriptions," and the pharmacy was just dispensing the drug, that's one thing. But if the pharmacy was complicit at all in prescribing this drug to him, could the pharmacy face charges?
Callan: It's a very hard case against the pharmacy, because they always have the excuse, "Hey, a doctor prescribed this; it's not our job to second-guess a doctor's judgment." And after all, the pharmacy doesn't know where the propofol is being administered, so unless they're on the take or there's bribery or something going on in the background, it's a very hard case against the pharmacy. I think the case will stay on Dr. Murray.