This is a rush transcript from "Hannity," April 16, 2013. This copy may not be in its final form and may be updated.
SEAN HANNITY, HOST: Now to someone who knows all too well what the aftermath of a tragedy like this is like, former New York City Mayor Rudy Giuliani. Who can forget his incredible leadership during America's darkest hours. He rallied a city and a country in the aftermath of 9/11 and worked tirelessly to get the city and its people back on its feet.
Just moments ago, I spoke with the mayor about the latest developments and what this means for this investigation.
HANNITY: Joining us now former New York City Mayor Rudy Giuliani. Mr. Mayor, good to see you.
RUDY GIULIANI, FORMER NYC MAYOR: Hi, Sean. How are you?
HANNITY: It would be foolish if we don't look at the ricin mail as connected, right?
GIULIANI: I was taught you investigate by not excluding coincidences. When you have a coincidence, it's probably connected. If it isn't connected, you can find out. All of a sudden getting something like in this sent to the United States Senate, you have to start wondering, is this something being triggered here, something going on? It may turn out not to be so, but it's worth investigating it from that point of view.
HANNITY: We have all this break news tonight and I'm not sure how to interpret it. But good news I think in terms of the investigation. WAGA, our affiliate out of Atlanta, has what they believe is the pressure cooker that they got the tape of, and there it is up on the screen. Certainly that could be helpful to the police.
GIULIANI: Right. Tracing where it came from and trying to get back to who did it. The bad news is they let go of the guy that they thought was connected to this. Now, I mean that means they spent the first day, which is a critical day in any terrorism or murder investigation, they spent the day apparently chasing a wrong lead. Now maybe it isn't a wrong lead. Maybe they don't have enough and they are letting him go and they want to see what the heck he does. It's hard to tell because we don't have any of the information they have inside the investigation.
HANNITY: One of the things interesting to me, because we have so many more surveillance cameras, especially in a place of Copley Square, it would be the equivalent of Times Square in New York.
HANNITY: So we have more than we ever had. The interesting thing is they did use these bomb-sniffing dogs, which might shorten that timeline in terms of where they have to look.
GIULIANI: Right. This was put in right before the bomb actually went off.
You would hope one of those cameras picked it up. You have actually three sets of cameras you are talking about here. You got the government cameras, the ones that are up there all the time. You have the television networks that were covering the marathon, one doing complete coverage.
HANNITY: Right at the finish line.
GIULIANI: And then you have all the people with their camcorders taking pictures of their father, uncle, brother, their son. That's what they are calling for tonight. They are asking for those people to bring those in. I remember solving a couple cases that way when I was with the U.S. attorney's office. All of a sudden somebody had a picture of something and, wow, it proved the case.
HANNITY: What do we make? WHDH also, I believe this is the second bombing that went off, we will put it up on the screen next to where the mailbox is, if you look really, really closely here. They suspect that may very well be the second bomb. Now, if that's the case, and again, as you are pointing out, that would be another lead.
HANNITY: Now we just -- with law enforcement, and I would not blame them at all if they didn't tell us -- would they be less inclined to let the American people know whether or not they have an image of who this is?
GIULIANI: They might. They might. Look, suppose I say I've got an image of the guy who did it. What happens to the guy? He takes off like crazy, right? So, I mean, there could be a reason to keep this information confidential if you think you are going to spook the guy who did it and all of a sudden he's going to take off.
So they have to be allowed to mislead, even though from the point of the press and the public's right to know you say we should know all the facts. But they are looking for murders here. So misleading is a very acceptable part of law enforcement.
HANNITY: There's been a ton of irresponsible -- and I am not going to get into this deep tonight -- speculation on the part of the left. People like Barney Frank, Steny Hoyer.
GIULIANI: I know, hoping it's anti-tax and tax day.
HANNITY: It's just irresponsible.
GIULIANI: Look, none of us know who -- what is behind this. Is it ideological? If so, is it an Islamic terrorist or some other kind of ideology? Is it some crazy person? We're going to find out. If you go by the odds, how often have these things been done? Then of course you will lean in the direction of somehow is it Islamic related or Jihadist related, just taking the percentages of bombings of that taken place, one group, another group, another group. But hey, that doesn't prove anything.
HANNITY: And it could be homegrown.
GIULIANI: My hunch is it is homegrown.
HANNITY: Explain what that means when you say homegrown.
GIULIANI: I don't think this is orchestrated by Al Qaeda or any of their off shoots in Africa or places from there. I think if it was, we would have picked it up because it would have to have been communicated internationally and the coverage now is immense. It sounds to me like this was more homegrown, like Major Hassan, like the attack in Britain '05.
I was in Britain a half a block away from the Liverpool Station when that went off. Those were homegrown people, which is why they eluded the British intelligence service, which is the best in the world, because they were looking at people who came from overseas. They weren't looking at their own citizens.
This is my hunch. I could be absolutely wrong. But if I were investigating this, that's the hunch I would be working on.
HANNITY: The last thing, something you said this morning, you were surprised that we have not seen more of this. Is this a preview of what you think is a coming attraction?
GIULIANI: This was a nightmare that I had and my police department had for at least a month, month and a half after September 11. When the anthrax attack occurred one month after September 11, we were sure that was the shoe that dropped. When the plane that went down two months later in Rockaway, there it is, that's the other attack.
Years we have been waiting for this. We have stopped a lot of it. Our intelligence gathering, our intelligence analysis is much better now under both Bush and Obama than it was before September 11. So we have thwarted a lot of this. But if they decide to do things like this, this is very, very hard.
HANNITY: The U.S. could become Israel. Scary.
GIULIANI: Yes. I mean, who has better defenses than Israel? And they were only able to prevent a certain number of them. If these people are willing to do this, this is going to be very hard to prevent.
HANNITY: Mr. Mayor, thank you so much.
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