This is a rush transcript from "On the Record," July 1, 2011. This copy may not be in its final form and may be updated.

GRETA VAN SUSTEREN, FOX NEWS HOST: Forensic pathologist Dr. Michael Baden joins us to talk about the evidence. Dr. Baden's wife is a former member of the Casey Anthony defense team in this case.

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VAN SUSTEREN: Dr. Baden, nice to see you.

DR. MICHAEL BADEN, FORENSIC PATHOLOGIST: Good to see you Greta.

VAN SUSTEREN: In a perfect world with a fully professional autopsy, if you found those remains of that child six months after she died, and if it sat out in the open sun and maybe in swampy waters, is there some diagnostic test or autopsy means by which you can determine whether she died from drowning or suffocation?

BADEN: Yes, the diatoms. If she drowned, then the diatoms in the bone marrow which they examined. But they examined it for toxicology not these one-sell plans, can tell which body of water, pool, lake, and a bathtub that she may have drowned in, if she had drowned.

VAN SUSTEREN: You say diatoms. What is that, number one? And number two, you say it can tell. Are you saying it would tell with certainty?

BADEN: If it is positive, it is with certainty. Diatoms are like plankton, one-cell plants ubiquitous around the world. There are a few thousand different species. Normally, one can take water from whatever body of water and find four, five different species in the water that's like a fingerprint of the water.

If that's inhaled into the lungs, into the body, that goes by the bloodstream into the bone marrow so that after death if the bone marrow is examined and has the same five species as in the water, that indicates that child had inhaled that water and is evidence of drowning.

VAN SUSTEREN: One thing the viewers should know, and this is probably the dirty secret about trying cases, the gamesmanship between defense and prosecution. Sometimes both sides don't want a principle analyzed because they are afraid of what the result will be. In this instance this diatoms is that something every medical examiner knows about that should have been done here?

BADEN: I think all medical examiners know about it. I think it should have been done. As you indicated, maybe the prosecutor didn't want to do it. Maybe the defense didn't want to do it because they didn't want the results. But it could have been done, it should have been done and it want done.

VAN SUSTEREN: When autopsies are done, medical examiners often times take tissue samples, and they save them. Would a routine sample kept from this autopsy had been saved so it still could be determined?

BADEN: It is possible if they saved a part of a bone or a whole bone. The remains were given back to the family and I understand cremated. Since this is a case that isn't completed yet, maybe the toxicologist still have the bone marrow in their office that they did toxicology and didn't find anything and that could still be used for diatoms if it is still available.

VAN SUSTEREN: Was this autopsy professional or JV?

BADEN: It was professional, but it was incomplete. The head should have been looked at. I think, after all, there were no tissues. There was nothing to cut, except to open up the head that wind done. That -- you never know. When you open up the head, you look in and see the bottom of the skull and there's bones there, the ear bones, that in drowning can be very helpful in determining whether or not there was hemorrhage and whether or not the person drowned. It could be helpful.

VAN SUSTEREN: The prosecution has at least suggested or attempted to prove, the jury will make a determination, that the death was by chloroform, suffocation or a combination. Do you have a thought about that?

BADEN: Yes. I think that as things stand now from a forensic point of view, one can't distinguish between drowning and some kind of suffocation. There's no evidence of chloroform. This was tested for. I think the only evidence was Dr. Vass' sniffer machine, which I think is unreliable, unconfirmed new evidence that should never had been introduced.

There's no chloroform. The prosecution tried to say she made chloroform in her house. If she made chloroform in the house there would be an odor throughout the house. It's hard to do. The odor would stay for weeks and weeks if it were chloroform. And I think there is no evidence of chloroform. They did the hair. They looked for chloroform in the hair and they didn't find it.

VAN SUSTEREN: At least at this point, we are sort of left with a circumstantial case which can be as powerful as a direct evidence case. The jury will have to piece this together. Dr. Baden, thank you, sir.

BADEN: Thank you, Greta.

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