This is a partial transcript of "The Big Story With John Gibson," January 23, 2007, that has been edited for clarity.

JOHN GIBSON, HOST: The "Big Debate" tonight: Should male sex offenders be castrated?

Lawmakers in Massachusetts are thinking about doing just that. It's proposed legislation that would allow the chemical castration of sex offenders. It's already legal in five states, including California. But is castration the best solution for stopping sex predators? Does it really work? With me now is Massachusetts state Representative Paul Casey, who filed this bit of legislation.

So Paul, there are other states, Texas, California, let me put up a map, show you where this is legal around the country: California, Texas, Illinois, Georgia and Florida. What's the experience there? Does it work?

STATE REP. PAUL CASEY, D-MASS.: Well, don't forget Montana also. But history proves that there is a five percent recidivism rate on those individuals who do get injected with chemicals to not only stop libido but certainly the testosterone. At that level, with zero testosterone, there's a pretty good success ratio.

GIBSON: There is a theory that sexual aggression, rape, sex offenders, has virtually nothing to do with the sex drive. It's another way of assaulting somebody. Do you buy into that theory?

CASEY: Again, I'm not an expert on this. But the reason why we're issuing this in Massachusetts or attempting to pass it is just to have one more tool in the arsenal to be able to oppose or fight these predators. It's all about the protection of the kids.

What do you do when they get out? It's not that we're trading your sentence, your long sentence, for an injection. What we're saying is the injection in conjunction with the sentence — and maybe it is a lighter sentence — but when that person gets out, what's the best shot for society to stop that recidivism?

GIBSON: Paul, if you're going to go for chemical castration, why not surgical?

CASEY: Great question. You can invite anyone from the ACLU to debate that question but this is strictly voluntary. So it would be something that would be established similar to California and it's done on a voluntary basis. You can't just suddenly maim somebody and think that there's not going to be lawsuits or that that's a long-range plan.

On the chemical basis, it's a voluntary type of thing. Yeah, there are incentives: You will get a shorter sentence, but at the same time you're going to have a monitoring system and more importantly, it's not too onerous for the state and it saves money at least in terms of incarceration. There's no question about that.

GIBSON: What is the reaction up there? Is this something that's getting support in Massachusetts?

CASEY: I think it's a hot-button item right now. People are mistaking it for saying, well you're going to be looser on crime. It's ironic because actually this is a tougher on crime measure because it's done in conjunction with so many other elements.

I have sheriffs of Worcester County, sheriffs of Middlesex County, Jimmy DiPaola, begging for something like this because they truly believe that it will be a great, great effect against the recidivism rate and they're saying, give us more tools, Casey, please. And then again, it's another arrow in the quiver against these predators, these animals who are preying on our young and the most innocent victims.

GIBSON: Paul Casey, Massachusetts state representative. Mr. Casey, be sure to keep us up to date on this. Thank you.

CASEY: I really appreciate it and if you're a parent I would absolutely...

GIBSON: Thank you, Paul. I've got to run. I see it there. OK, good, we'll get that on next time.

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