[Anderson Cooper, Ac360:] Now, as you know, there was no Dashcams so investigators can't see what happened but perhaps, they can hear what happened. The FBI is analyzing the alleged audio recording of the shooting which someone who lives near by says he just happened to capture wall video chatting. Ted Rowlands has more.
[Ted Rowlands, Cnn Correspondent:] It's this critical moment caught on audio tape and it could be a key piece of evidence as investigators work to determine exactly what happen between Michael Brown and Ferguson Police Officer Darren Wilson. The shots can be heard in the background of an online video chat.
[Paul Ginsberg, Forensic Audio Experts:] It's electronic. It's objective. It doesn't take sides.
[Rowlands:] Forensic audio expert Paul Ginsberg analyzed the nine second clip and creative a wave form graphic highlighting the gunshots. He count's a total of 10 shots within approximate three second pause after the six shot. Take another listen. The three second pause could be very significance.
[Ginsberg:] It could be depending upon what the witnesses say they saw and what's in the police report.
[Rowlands:] Several of the witnesses do mentioned a pause.
[Unidentified Female:] They shot him and he fell. He put his arm up to let them know he was complying and that he was unarmed and they shot him twice more.
[Dorian Johnson, Michael Brown's Friend:] And he put his hands in the air and he started to get down but the officer still approach with his weapons drawn and he fire several more shots.
[Rowlands:] An independent autopsy determine that Michael Brown was shot at least six times all to the front of his body. The other four shots heard on the recording could have missed. The man who inadvertently recorded this audio wants to remain anonymous. He lives in one of these apartment buildings which as you could see is very close to where Michael Brown was shot and killed.
[Lopa Blumenthal, Attorney:] He was in his apartment, he was talking to a friend on a video chats. He heard loud noises and at the moment at the time, he didn't even realize the import of what he was hearing until afterwards.
[Rowlands:] The recording could prove critical. Should this go to trial, a tool both the prosecution and the defense could use to bolster their case.
[Ginsberg:] This has a bearing on really everything else. This is a piece of the puzzle that has to fit.
[Cooper:] And Ted Rowlands joins now live from Ferguson. Our investigator are saying anything publicly about this argue?
[Rowlands:] No. They're not Anderson. The attorney that's representing the man that recorded this audios has said that her client has met with the FBI, has been interviewed by the FBI and the FBI has a copy of this audio and is presumably analyzing it, looking for anything significant.
[Cooper:] All right. Ted, appreciate it. Joining my now live, our CNN legal analyst Jeffrey Toobin and Sunny Hostin, both former federal prosecutors and Frank Piazza, an audio forensic expert. I appreciate all of you being with this. Jeffrey I haven't talk to you. What do you make of this tape? How significant you think it is?
[Jeffrey Toobin, Cnn Senior Legal Analyst:] Well, I think it's certainly good for the investigation that exist. I mean assuming that it's authentic and I think besides point that way, it is an objective piece of evidence that will guide the investigators and, you know, help them figure out what happen. I don't think it really I think both sides could use it on. I don't think it proves guilt, proves innocence. It's a piece of the puzzle. The defense, if there is a defense. Well, Officer Wilson could say, look it shows he was pausing and yet Mike Brown keep coming. The prosecution could say, it shows that he kept firing even after he had hit him a couple of times which shows, you know, his aggressive attitude. I think it's an important piece of the puzzle but I don't think it seals anything.
[Cooper:] Sunny, you assuming this is a legitimate tape and again, it's being analyze by the FBI. You believe the pause is significant...
[Sunny Hostin Cnn Legal Analyst:] I do.
[Cooper:] ... because it backs up the eyewitness.
[Hostin:] I do because I think eyewitness testimony alone is troubling because there has been some inconsistencies that I think they've been made too much up. But I think, when you hear the pause and so many of the eyewitness just say he stop shooting, Mike turned around, put his hands up and then the officer continue to shoot. That I think is very powerful collaborative evidence and that's the type of evidence the prosecutors look for.
[Cooper:] Frank, how does the FBI go about authenticating this? Is there a lot of data that comes along with the tape like this?
[Frank Piazza Audio Forensic Experts:] Well, you know, first thing the FBI is going to need to do is get a hold of the original recording and if this was done with some sort of video chat then they have to have access to that account, the person who was speaking the male voice, you know, he has to be able to enable them to get that exact original copy and I'm curious to know about the other side also who was part of that video chat, let's get a copy of that. That at least get a start to knowing we have the original recording as opposed to something that's possibly have been passed around at this point right now.
[Cooper:] Is it possible that there is more on that tape that we don't hear just in the playing of it that there's maybe I mean is there any way to kind of analyze background more? You see that in movies a lot.
[Piazza:] Yeah. You can. There's been a big discussion about the pause in the tape. You know, well I'd be curious to know if I had an opportunity to enhance it and analyze it to see maybe if there's something buried in there. You know, what's interesting, again, I haven't heard the recording fully examine but those gunshots are pretty loud which tells me that the microphone have the ability to pick up other things that might be outside that building. I don't know that but I'd like to have the opportunity to bring that out.
[Hostin:] Yeah.
[Cooper:] Let's play it again.
[Toobin:] I've to say I don't think that pause sounds so long. I mean there definitely is a pause.
[Hostin:] Three seconds.
[Toobin:] But three seconds, you know, in the calm reflection sitting here weeks later.
[Cooper:] [inaudible] in the heat of the moment, three seconds quite wide.
[Toobin:] Right and, you know, in a life for that situation, adrenaline flowing on all sides. You know, I'm not sure ultimately a jury will find that pause all that significant. I mean it doesn't mean Officer Wilson is guilty of crime or not. I'm just not true that pause is all that significant.
[Hostin:] I disagree because I've had cases where there have been police in [inaudible] shootings but shooting and we know that the shootings occur very, very quickly. It's usually rapid fire and the three second pause with the trained officer who was trained to asses threats, who was trained to de-escalate force, who was trained on the continuum of force requirement. I think a three second, if you have an expert to testify about that three second pause I think it actually can be quite strong.
[Cooper:] Frank, how long does examining a tape? The authentication process and really trying to get everything you can from the tape, how long is that takes? Is it a long process?
[Piazza:] It is. It's long and then you would think, OK. So we're listening to what a 15 second clip approximately. There are many areas in that recording that you have to pay attention to, one being the male voice that you hear, another being the gunshots, another being the environment where the microphone is actually making the recording. You have to confirm that all of those are continuous and kind of a linear, kind of way. That's part of...
[Cooper:] So make sure there's not any edits in it.
[Piazza:] Absolutely correct.
[Cooper:] And that's something you can determine?
[Piazza:] Usually the answer is yes. There are signatures especially in visual recordings, recordings that are made with an AC current in the room. I know this is, you know, a little geeky but there are things there that you can identify. There are signatures whether or not this has or not, I don't know. But also as a digital file, there is meditated too that goes with it. For example, the time and date stamp. There are ways to know that if this video chat software whatever it was, you know, is reliable and has consistency...
[Cooper:] So it would have the time and date. So they could theoretically find out what time exactly this was recorded and compare that to the what would the known time of the shooting.
[Piazza:] Oh, sure. It would definitely be time stamped. That's my opinion.
[Toobin:] And, you know, what somewhat of what Frank is saying is the reason I think the October deadline that the prosecuting attorney has said...
[Cooper:] For the grand jury.
[Toobin:] ... for the grand jury. I think that's optimistic.
[Cooper:] Really?
[Toobin:] Yeah. Absolutely. You know, this is complicated and this is just one part of the investigation. It's not the ballistics. It's not any DNA that might be found on the gun. Far better I think take another month.
[Cooper:] We don't even know if they have found all the bullets. I mean we don't know...
[Toobin:] Absolutely.
[Hostin:] I'm sure they have. But I've got to disagree with you because this is not a who done it case. This is not a complex case. I think certainly the audio tape adds a wrinkle but let's face it and you know this Jeff, prosecutors don't want to put on a lot of evidence in the grand jury because that evidence can be use at trial and so typically you streamline your case, it's very easy to get an indictment, especially the shooting case.
[Toobin:] But the prosecutor has said, "We will put every piece of evidence in the grand jury."
[Hostin:] And that is very unusual...
[Toobin:] Which it is unusual but that's what he said and there's going to be a lot of evidence.
[Hostin:] That's why I think this is very troubling. It is not the norm in my experience and I again, think that it is very surprising that he chose to go the grand jury route, chose not to recuse himself and have a special prosecutor and chose not to just bring this, charge this case, bring it in front of the judge and let the judge decide.
[Cooper:] He doesn't say that ultimately all the evidence presented will come out.
[Toobin:] Right and that's a lot of evidence and it's going to take some time and I think October is not going to happen.
[Hostin:] And that's bizarre. Prosecutors never do that.
[Cooper:] Sunny, thank you. Jeff thanks. Frank Piazza, thanks very much.
[Piazza:] Thank you.
[Cooper:] A really fascinating stuff. Just ahead, there may not be so many questions about exactly what happen to Michael Brown if the whole incident was recorded by dashboard camera which it wasn't. We'll take a look at some cases where dash cams have cleared police of wrong, doing or caught them using excessive force, next.