Brian Laundrie likely never left the Florida nature preserve where he was last seen - and with the discovery of his remains earlier this week, it brings to an end a manhunt that has captivated the country.

But - even so, there are unanswered questions in the disappearance and death of Gabby Petito. This week on The Debrief Podcast, Pei-Sze Cheng revisits experts about the latest in the case and where they think we're headed next.

Download this week's episode of The Debrief on Apple Podcasts, Stitcher, Spotify or wherever you listen.

The following transcripts transcript have been lightly edited for clarity and concision.

Inside the Forensic Investigation

Joseph Scott Morgan is a professor at Jacksonville State University, former medical examiner and commentator based out of Alabama. He breaks down how authorities were able to so quickly identify Laundrie's remains.

Pei-Sze Cheng: Joe, we spoke to you when Gabby's autopsy was revealed, but now we're learning new information about Brian. These remains were identified today through dental records. How accurate is that?

Joseph Scott Morgan: Oh, boy, it's very accurate. And can you let me expand on this and how significant this is?

Sure. I'd love to hear it.

Well, first off, dental ID has been around for a long time in our field. It's something that we can go to that is scientifically based. It's not like facial identification because you have pre-existing or antemortem records that would be at the dentist office.

That piece of this is very significant, Pei-Sze, and I'll tell you why. The fact that they were able to turn this around so quickly tells me as an investigator, that they had already reached out to the dentist some time ago. When we have a body that is unidentified, we'll have to go through all manner of hoop jumping and this sort of thing to get records. They turned this around in less than 24 hours. That is very significant, that means that they were sitting on go.

My suspicion is that the FBI, along with the local authorities, they went to the dentist. Sometimes a dentist will require a subpoena. Sometimes they're more cooperative, particularly if they know what's riding on something like this, and this is what's happened. They had it standing by. And here's the other thing, they would probably have had to called in a forensic dentist, otherwise known as a forensic odontologist. Now they deal in bite marks, but particularly they deal with unidentified bodies and examination of post-mortem dental remains, which is what we're dealing with here. And they were able to very quickly turn this around and get Brian Laundrie positively identified.

So, you're saying that it's very accurate. Because there are a lot of people on the internet who are saying, "oh, this is just another ruse. It can't possibly be him." But you're saying dental records are pretty much airtight.

Think about the last trip you took to the dentist. It doesn't matter even if you've had braces when you're a kid, everybody's dentition is unique to them. When you take that uniqueness that you're born with and you put wear on those teeth over a lifetime, all the rotations, malocclusions, all of the cavities that have never been treated, those that have been treated, tooth extractions, caps, bridges, all of these things, extractions of molars. I mean, how many of us have had our wisdom teeth taken out over the years?

Each one of those points along that continuum are unique. That's why it makes it so very difficult. And I would assume that people are saying that they have faked the dentistry in this, I have no idea. But that's what makes it so unique to each individual. So, unless some, ne'er-do-well out there has access to a great science and they're able to go in and create some kind of faux dentistry, this is him. It's going to be right on the money.

Now these remains that were described to us as partial skeletal remains. And that even a part of a skull bone was discovered. One question that a lot of people had was, if you were in the preserve for let's say five weeks, if that's the estimated time, would the body decompose to that point where it's skeletal remains?

Most definitely. Remember we're dealing with high heat and high relative humidity. A body in this harsh environment is going to decompose more rapidly than say for instance than somebody that's up on the Canadian border, where the temperatures at night tend to be cooler.

Many of us have been to Florida. You know how miserably hot it can get during the summertime. And he's not on the coast. He's not near the beach. He's in a marshy area. It's hot. It's humid. There's a lot of greenery. You've got a lot of low growth and then you've got a lot of canopy in there too. So, it's holding in the heat and this is like being in a convection oven essentially. And it begins to render the body down over a period of time.

Pei-Sze, one thing that is very significant here that this is a partial skeletal remains case. That's significant because we have to begin to think about scavenger activity. We also have to think about what kind of toll the environment has taken on the body. Sometimes bodies will just literally come apart. We don't know what's missing.

Also, we have to factor in this idea that they said the body was submerged or partially submerged. So now you've got current potentially, at least a small amount, as the water rises and falls. Are remains being swept away?

I don't know, they have not answered to that question. And this is, this is kind of the thing that really grabbed me when I heard this, I'm glad you brought it up. They talked about the skull. Now, tell me again, precisely. What was it that they said about the skull?

They said it was a partial human skull.

Partial human skull, what does that mean? Let's think about that.

We have to include the jaw. So, if we include the jaw in this idea, was the lower jaw missing? Because it can become disarticulated at the TMJ, right? That's standard. But also another factor -- was there trauma?

When we're being formed in development, we have what are called suture line that kind of fuse our skull together. Sometimes those areas can become weakened, particularly in this very hostile environment. Sometimes they will come apart. From a forensic standpoint you have to look at, this is the skull in a partial state just to give a little latitude with that term.

Is in a partial state because there was some kind of antemortem - which means pre-death - trauma that caused a defect in the skull? Or is this something that was post-mortem, maybe animals involved with the skull, that created the situation where the skull is only partially intact?

That's one of the things that both the forensic pathologist and the forensic anthropologists are going to be trying to determine back at the medical examiner's office and maybe at an anthropology lab where they can really study this very closely.

They're going to be looking at specific fractures, trying to determine and estimate how long this has been in dwelling in a spot. Was it again before death or was it after death?

So, we're looking a decomposed body to a significant degree. Do you think Brian was in this preserve the entire time?

That's hard to answer, but I will tell you as a forensic scientist, that is certainly a question I would ask.

I was thinking about this, Pei-Sze, when the news came out. Does this marry up with the timeline when he was last seen alive?

Is it possible to go down range in linear time to try to decide if he has been down this long, or was it a period of time where he may have survived out there, lived for a while, maybe one to two weeks down range and then death was visited upon him either by his own hand or some accident, active nature, or maybe some other person.

I have no way of knowing. But that's something else that they're going to be exploring because I can tell you people like you are going to be asking the medical examiner and the forensic anthropologist those specific questions.

Because let's face it, everybody wants to know. I want to know. I want to know if this does marry up.

One of the biggest points of contention throughout this entire event has been the timeline, confusion, not knowing where he is, this idea of "when was he last seen? When was he last spoken to?"

He kind of just disappears off the face of the planet. And it's only going to be through science that we're going to be able to answer this question in the physical body.

Also, any information that the feds currently have that we're not aware of relative to tracking him digitally. I think that's going to be a key as well, because I don't necessarily know that they've released all of the information in their investigation. I would suspect they probably haven't. 

Why the Search Took So Long

One question that many are asking: why did the search for Laundrie take so long with so little success? Craig Caine, a former U.S. Marshal who oversaw the New York/New Jersey Regional Fugitive Task Force gives insight into manhunts like the one for Laundrie.

Pei-Sze Cheng: I'm back here in North Port, Florida, as you can see. A couple of weeks ago we had actually spoken and you had said you didn’t think he was in the Carlton Reserve and that you think he is alive. So now with what happened this week. What do you think of that?

Craig Caine: You know, we could speculate from now until the cows come home. I believed he was in the preserve at some point in time, but I believed that he was being helped. And I did believe that he was local. That being said, there's a lot of moving parts going on.

Let's just talk about how they've found these items. The police and the FBI had been searching what seems to be every inch of this 25,000 acre nature reserve in the past month or so.

They haven't been able to find anything since day one. Then, the Laundries say, "we're going to go and look," they bring the FBI there and they find a backpack. The other belongings of Brian's and some human remains. Everyone I've been speaking to says the timing seems suspicious. What do you think?

It's very fishy to me, that whole scenario. It just kind of reinforces my belief that the parents knew where he was all along. And this is just purely conjecture on my part.

But the fact that they actually brought law enforcement to that specific site kind of leads me to believe that whether they were helping him or not, that I don't know. But, you know, it's possible that they helped him in the very beginning when he first went into that preserve four or five weeks ago.

They're going to cover every inch, every millimeter of that area, where the body was found. Then they’re going to gradually fan out and make a perimeter. At some point, when they feel comfortable, that that's going to be the end of where he could have been or parts of his skeleton or body has been found. But they're going to be looking for any kind of material evidence.

But se no matter what they find it's still not going to bring closure to Gabby's family. They're never going to know, you know, what prompted him to kill her, how it was done.

Why, where and how and all that sort of stuff. It would have been nice to capture him alive and hopefully they would've got a confession out of him or he could have given the family or law enforcement some kind of answers that could have bought some kind of closure to the family.

Unless he left some kind of testimony, I just don't see how they're going to know the circumstances of what happened in Wyoming.

Well, we don't know the condition of the notebook at this point. If it was indeed submerged underwater, it could be illegible. And you wouldn't be able to read it?

Excellent question. Yes. That was another point that I was going to bring out. We don't know if he was in that particular area and then the flood came in, the water came in, it rained.

Everything everybody thought about this case turned out to be a lot different. I always say "investigators are humans." They're going to make mistakes - not that I believe there was any mistake made here.

You could search a house for a fugitive and not find them and he's in the house. And that happened plenty of times where he's right under my nose, hiding in a crawlspace in the attic. There were circumstances we had people hiding under mattresses in between televisions. They had a hollowed-out televisions back where the sky would crawl on display.

So that being said, that's just the house. Now you're talking about a nature preserve. Law enforcement could have walked past that area a dozen times. And depending on the circumstances, might've walked right past him. It happens.

Where the Case Goes Next

Despite the discovery of Laundrie's remains, the case of Gabby Petito isn't closed just yet. Weysan Dun is a retired FBI agent with more than 30 years of experience working complicated cases. He gives insight on what authorities might look into next.

Pei-Sze Cheng: So, where does the investigation go from here? Is the FBI still going to be the lead investigator or does it go to North Port police now because Brian was found here?

Weysan Dun: Well, that's a very complicated question. As far as the FBI's involvement, I think a lot will depend on whether there are any potential additional federal crimes that might be investigated.

If there are, then the FBI potentially will stay involved unless all crimes that may have been committed are believed and suspected to be only committed by Brian Laundrie.

But as long as there are investigative leads that have not been covered and potential crimes that could still be investigated, there is a potential that the investigation could go on at the federal level. The other possibility is that the FBI traditionally will assist state, local and county police departments when requested to do so. So, if there is any local investigation that continues and they need some of the resources and tools of the FBI, that could continue FBI involvement as well.

However, certainly from the news reports I've heard it like sounds like any investigation directly involving Brian Laundrie probably has come to an end with the confirmation of his death.

So, at this point, do you think that the FBI or any other investigative body would be able to find out what happened on this trip?

It's going to be a real challenge. First of all, there's the potential there may be some forensic evidence and forensic leads that could still be followed. Although that seems remote, quite candidly. The other possibility is if there are other eyewitnesses or people who may be tangentially aware of things.

Now that the case has become more public, if additional people come forward, potentially that could leave to a solution. But this is a challenging case and a very unusual case.

Certainly, if the victim and the suspect or perpetrator are both deceased, that really limits the ability to move the investigation forward.

Wow. And what about the parents' involvement? Brian Laundrie’s parents is it possible that the FBI would be investigating what role they may have?

Potentially, if there is an indication that they have been involved with a federal crime, or if a state or local agency requests FBI assistance, that certainly would be a possibility.

There's been a lot of speculation about that. The only thing I can say on that regard is that the fact that it's confirmed that Brian Laundrie is deceased certainly makes it more challenging. One could say even if the parents were involved, it would seem unlikely that they would be involved in the death of their own son, but you never know.

Well, not even just his death. Did they know when he came home that Gabby was in trouble? Did they have an obligation to report that?

That would be one avenue investigation that may still remain. That would probably be more on a state or local level.

But again, if there is any indication that they were aware of or participated in obstruction of justice related to a federal crime, then that aspect certainly could still be pursued.

At this point people are hoping to find out what happened in Wyoming. What happened between the time that they last heard from her and the time that he came back to North Port? Is there any way for them to find out?

Well, potentially. It's going to be really challenging. If there are no other people that come forward that have information, if nothing is brought forth by someone else who has the information, the only other possibility might be a forensic examination of digital data, forensic examination of cell phones.

But again, those are long shots. It all depends on whether the individuals had their phones with them, whether they were on or off and things of that nature. Sogoing forward is it is going to be very, very challenging to move this investigation forward if at all.