[Blackwell:] Welcome back. I'm Victor Blackwell here in front of Dallas police headquarters. The police are defending their use of a bomb and this bomb-carrying robot to kill Micah Johnson after that standoff with officers. It really is a first of its kind takedown. Dallas police say they used a robot like the one you see here as a last resort. This was after negotiations failed and the gunman kept shooting at them. Johnson ambushed and killed officers during an anti-police brutality protests on Thursday, spraying bullet into the crowd. He hit two civilians, hit 12 officers. Five of those officers were killed. Now, Sara Sidner is here with me. First, they're defending it against whom or what?
[Sara Sidner, Cnn National Correspondent:] It's an interesting question, because it isn't as if there is a large groundswell of people asking, why did they use this? There's a lot of people who recognize that the situation was extraordinary and they used extraordinary means to deal with it. So, we should be clear about that. But there's always the question of the slippery slope. When these should be used, since this has likely never been done before, exactly how they will use it and what are the decisions going into using something like this which is obviously going to create quite a bit of damage and kill whomever is anywhere in the vicinity of that blast radius. Let's talk a little bit about the actual device that they use. It was a remote tech, model F5, with a claw and arm extension, and on that claw and arm extension, it had C4, a whole pound of that explosive substance. That can do quite a bit of damage. It obviously ended up killing the suspect in this case. We should also mention exactly when all of this was going on. If you listen to what the police said, there were four officers who had already been shot and killed. And there was an officer who was likely killed during the negotiation which went on for hours. At some point the police decided, we have to do something or more officers are going to die. Here is what the police chief said about why they used this device.
[Chief David Brown, Dallas Police:] We saw no other option but to use our bomb robot and place a device on its extension for it to detonate where the suspect was. Other options would have exposed our officers to grave danger.
[Sidner:] So you heard there, it would expose our officers to grave danger. There will be questions going further about this. But I think in this particular situation, a lot of people are looking and saying this does appear to be their last resort.
[Blackwell:] Yes. Sara Sidner, thanks so much. Let's expound this conversation now. I want to bring in Jeff Parks. He is homeland security and improvised explosives expert. He also served in the Army. Thank you for that service and thanks for being with us this morning, Jeff.
[Jeff Parks, Homeland Security And Improvised Explosives Expert:] Thank you. Good morning.
[Blackwell:] So, first, when Sara said remote tech model F5 with a claw and arm, I have to admit I glazed over a bit. I need for you to as plainly as possible in just a few seconds if you can explain what this is, what it's typically used for, because this use is a first of its kind.
[Parks:] Bottom line is it's a remote controlled vehicle that's driven by an operator through a camera feed. It has a manipulating arm which is able to pick things up, put things down, extend and carry a package as it did in this case.
[Blackwell:] All right. Thank you for that. Jeff, we hear now that the chief is defending the department's use of this robot and the bomb to kill the shooter. What do you think of the chief's decision to send in that robot?
[Parks:] I think it was an excellent decision. I think the robot is there for high risk situations. In this case, it was carrying the explosive. That's actually one of the things these are designed to do. The difference was that you had the chief had made a decision that lethal force was authorized and they used it to carry the explosive to the shooter versus normally where it may be carrying it to another explosive device that you're going to disrupt.
[Blackwell:] So less than a pound or roughly a pound of C-4 used here that was detonated to kill this shooter, can you put that explosion into context for us? I mean, without being too graphic and indelicate because of the hour, but put the explosion into context.
[Parks:] I would say that's a significant amount of explosive. It was more than enough to do the job to neutralize this individual.
[Blackwell:] OK. OK. Now the question is, this is a first. Does this lead potentially for this to happen more often? That this would be a more common use of this technology? What's your concern or do you have a concern about the possibility of this becoming more common?
[Parks:] Victor, I think the key here was the unique part of this was you had a mass casualty situation. You had a police chief who had been forced to make the decision that this lethal force was authorized. And that's where police forces don't frequently go. So, that makes this more unique than the delivery method when was the robot. Once that decision was made, they had to eliminate this guy. You could use the robot or have to send a SWAT team. You wouldn't know, the SWAT team could have encountered improvised explosive devices, other bobby traps, and this guy was clearly well positioned. So by using the robot and a large amount of explosive, it kept them from putting those officers at risk. I don't think it's a slippery slope. Again, this robot is designed to investigate and carry a package or a bomb as it did here. So, the difference was not what it was carrying, but where it was carrying it.
[Blackwell:] All right. Jeff Parks, part of the conversation this morning as the chief here proactively defending the use of the robot and the bomb here, as Sara Sidner just told us a couple of moments ago, not specifically questioned or challenged by any specific entity, but part of the explanation of what happened here. Again, Jeff Parks, thanks so much.
[Parks:] Thank you.
[Blackwell:] All right. So, this week the country really was torn from within by violence, carried out by police and carried out against them, we should say. The police chief here in Dallas says his profession is hurting.
[Reporter:] Standing at a podium just hours after five of his officers were killed and seven others wounded by sniper fire, Dallas Police Chief David Brown speaks for them all.
[Brown:] All I know is that this this must stop.