This is a rush transcript from "On the Record ," May 21, 2008. This copy may not be in its final form and may be updated.

GRETA VAN SUSTEREN, HOST: Tonight, there is breaking news. Sergeant Drew Peterson arrested on a gun charge. Plus, Peterson is a suspect in his wife number four, Stacy Peterson's, disappearance. Stacy vanished October 28, 2007. And Peterson's wife number three, Kathleen Savio's, March 1, 2004, death has recently been reclassified as a homicide and is being investigated.

The spokesperson for the Will County state's attorney and Sergeant Burek of the Illinois State Police spoke earlier about Peterson's arrest at a press conference.

(BEGIN VIDEO CLIP)

CHARLES PELKIE, WILL COUNTY STATE'S ATTORNEY'S OFFICE: The Will County state's attorney's office and the Illinois State Police announced today that a charge of unlawful use of a weapon has been filed against Drew Walter Peterson. The charge alleges that the defendant knowingly possessed a rifle, namely, a Colt model Sporter (ph) lightweight with a barrel less than 16 inches in length, in violation of Illinois state law.

Peterson was arrested by Illinois State Police in Bolingbrook this morning. Bond was set at $75,000. He posted 10 percent, $7,500, at the Will County jail to secure his release while he's awaiting trial.

Unlawful use of a weapon is a class three felony that carries a penalty of up to five years in prison upon conviction. The rifle was one of a number of weapons that were seized from Mr. Peterson's house during the execution of a search warrant back in -- on November 1 of 2007.

We're available to answer a limited number of questions.

QUESTION: His attorney, Mr. Brodsky, says the state police are just harassing him. What do you say to that, sir?

SGT. THOMAS BUREK, ILLINOIS STATE POLICE: No, we determined that the weapon was illegal. The barrel is under the 16-inch length. And an arrest was made today.

QUESTION: (INAUDIBLE) quote, unquote, "a technicality," to drag him into jail and do all the media horde, and so on, would that be, in your mind, harassing him? Are you trying to get him to talk?

BUREK: Absolutely not. That weapon was illegal, and it was determined to be so, and he was arrested.

QUESTION: Was it modified by him? Because Joel Brodsky is saying this was his SWAT service weapon. He's done no modification to it, and he's allowed to, as a law enforcement officer, have weapons that are under the length specified...

PELKIE: At this point, we can't comment on that, but what we can say is that is an illegal weapon. He's not allowed to possess that weapon. You can't possess that weapon in the state that it's currently in.

(CROSSTALK)

QUESTION: You've had the gun since November, and he's saying, Look, you've had it six months. Did it take you that long to figure that out?

PELKIE: No, absolutely not. We've known it was illegal since shortly after the gun was taken into possession by the Illinois State Police.

QUESTION: Then why today?

PELKIE: At this point -- you know, initially, the determination was made not to file a charge in that case, and that's not uncommon when you've got a broad investigation, and we've got two investigations that are going on right now. The determination was made early on, you know, not to charge the case, but now, you know, we're faced with the potential that an illegal weapon may be put back onto the streets, and we can't allow that to happen.

(END VIDEO CLIP)

VAN SUSTEREN: What does Sergeant Peterson have to say about this new felony gun charge? Our cameras caught Peterson leaving the Will County jail.

(BEGIN VIDEO CLIP)

DREW PETERSON, SUSPECT IN 4TH WIFE'S DISAPPEARANCE: There's good news.

UNIDENTIFIED MALE: Wait, wait, wait, wait, wait!

PETERSON: I just saved a bundle on my car insurance.

(LAUGHTER)

UNIDENTIFIED MALE: Excuse us.

QUESTION: Drew, what do you think about all this craziness?

PETERSON: What?

QUESTION: What do you think about...

(CROSSTALK)

UNIDENTIFIED MALE: I'm doing well.

QUESTION: And what do you think of the charges?

UNIDENTIFIED FEMALE: Guys, give him some room.

QUESTION: Come on, tell us something.

QUESTION: Say something.

(CROSSTALK)

PETERSON: I just saved a bundle on my car insurance.

(END VIDEO CLIP)

VAN SUSTEREN: Sergeant Peterson's lawyer, Joel Brodsky, spoke earlier.

(BEGIN VIDEO CLIP)

JOEL BRODSKY, ATTORNEY FOR DREW PETERSON: They're alleging that Drew's AR-15, which was his SWAT duty weapon, is three eighths of an inch too short, the barrel is three eighths of an inch too short. However, that's not illegal under Illinois law because police officers' duty weapons are allowed to be non-conforming. After talking to the state's attorney's office this morning, it's my belief that they were not given full and accurate information prior to bringing this charge and that further investigation will result in this charge being dismissed.

QUESTION: The charge is a misdemeanor?

BRODSKY: No, it's a felony.

QUESTION: So what's your reaction to them bringing this charge on the day before he's supposed to get the weapons turned over to his son?

BRODSKY: Well, it's the same thing that they did with the EPO (ph) ID card the day before the weapons were supposed to be turned over to him. I think this is, on the part of the state police, another ploy to prevent the weapons from being returned. I do not understand why the state police can be so fixated on these weapons that they're willing to go to such extraordinary lengths to prevent it, but that seems to be the case.

You have to understand that he was a SWAT officer, and SWAT officers are allowed to have non-conforming weapons. They can have short-barreled weapons. They can have fully weapons. They can use, you know, the armor- piercing rounds. They're allowed to do that by state law, and Drew was a SWAT officer up until the day he resigned and this was a registered duty weapon. So I believe that when the full investigation is done, when they second check these things that I just informed the state's attorney of this morning, that I'm hopeful that these charges will be stopped.

This weapon was already in the possession of the state police before he resigned.

QUESTION: How did they come into possession (INAUDIBLE)

BRODSKY: They asked. They asked -- they took some of the guns, and some of the guns -- the rest of the guns were voluntarily surrendered 1st of November. He didn't resign until mid-November.

QUESTION: So he was never not a police officer when he possessed this.

BRODSKY: That's correct.

QUESTION: So there was never, in your mind, anything illegal about him having it.

BRODSKY: Absolutely not. And as I said, I do not believe that the state's attorney had full and complete information when they approved these charges.

QUESTION: Joel, what type of weapon is it again?

BRODSKY: It's an AR-15. It's an assault weapon, assault rifle.

QUESTION: Do you know if it's one of the ones that he surrendered or one of the ones (INAUDIBLE)

BRODSKY: I believe it's one of the ones he voluntarily surrendered.

QUESTION: Why did they wait until (INAUDIBLE) Talk about the timing.

BRODSKY: Yes, the timing is very suspicious, that they would wait until the day before we're going to get -- supposed to get the court order that the guns be returned to his son.

(END VIDEO CLIP)

VAN SUSTEREN: We asked Bolingbrook police chief Ray McGurry for clarification about the gun charge against Sergeant Peterson. Chief McGurry sent us this statement. "We believe Drew Peterson purchased that weapon, an AR-15, from a third party. Drew Peterson was not authorized to carry that weapon and it is not registered with the Bolingbrook Police Department. No police officer is authorized to carry such a weapon. However, a SWAT team member is, but that weapon must be brought in and inspected by our firearms expert to make sure it doesn't violate any state or federal laws. The serial number must be recorded, and they must pass a qualifications test. Mr. Peterson did none of these. Because it was altered, this weapon is a clear violation of any regulations, and Mr. Peterson was not authorized to carry that weapon. I challenge Mr. Brodsky to subpoena our records, as he has threatened to do. He will find no record of this weapon."

Now, Peterson's lawyer, Joel Brodsky, text-message our producer, saying the gun was registered as a second duty weapon with the Bolingbrook Police Department.

Joining us live in Bolingbrook is Mary Frances Bragiel, a reporter for WBBM. Boy, this is a battle of words, isn't it, between Joel Brodsky and the police department.

MARY FRANCES BRAGIEL, WBBM-AM: It certainly is. Once again, this has become a media circus out here, Greta. There is a lot of activity out here, and it all has to do with the media. And I got to tell you the only time we've seen Drew Peterson since he posted bond was two occasions. The most recent was about an hour ago, when somebody brought a gift basket by. He accepted that and got his mail, went back inside and avoided the media, Greta.

VAN SUSTEREN: Any idea who gave him this gift basket?

BRAGIEL: No, I don't at all. It was a young girl who appeared to come up here in the car. It was, you know, a fairly large gift basket. But he was happy to parade it back into his home in front of the media.

VAN SUSTEREN: What is his bail?

BRAGIEL: Right now -- right now, Greta, it appears we've got a car behind me. The alarm is going off in this interview here, so I don't know if he's doing that from inside the house or if a neighbor is doing that or what.

VAN SUSTEREN: Or maybe the producers are trying to steal the car.

BRAGIEL: Possibly.

VAN SUSTEREN: Well, that's an interesting touch. At least it's not a siren, so that's the positive part.

(CROSSTALK)

VAN SUSTEREN: Can you swing around, at least show us -- is that car right in front of Drew's house?

BRAGIEL: Oh, apparently -- apparently, that is (INAUDIBLE) apparently, that is Drew's car, I'm told by neighbors. So obviously, Drew may be watching this program right now and we're talking about him and talking about today's events, so...

(CROSSTALK)

VAN SUSTEREN: My money is on it that Drew has hit the -- has hit the key and sounded the alarm. That's a riot.

BRAGIEL: You think so? You think -- he is a funny guy, according to him, and this is how he handles the stress.

VAN SUSTEREN: Well, at least it's only 9:08 Central time, and so the kids in the neighborhood -- I don't know, is it school night there? I guess -- we have satellite trucks (INAUDIBLE) He's now added to the (INAUDIBLE) with the horn.

BRAGIEL: It's a school night here, but plenty of neighbors are out in this area, just watching what is going on. So clearly -- and it's a nice evening out here, so nobody's inside.

VAN SUSTEREN: Well, the good thing is, is that he can -- he can say that he doesn't want all the attention.

BRAGIEL: Oh, no. Are you kidding me? He loves all this attention. I'm sure he'll be out before the night's over, getting his mail once again.

VAN SUSTEREN: Well, he made a crack when he said something coming out after posting the $7,500 bond. He said he saved a bundle on car insurance. Is that the car he's talking about, I wonder?

BRAGIEL: It could be. He told me on the phone late this evening that he will never return a library book late, which is a joke, which is what he said initially when they had the search warrant last year, November 1. We saw him when he was walking around with that American flag around his face when he didn't want to be recognized. So here you go. It's off.

VAN SUSTEREN: All right. Well, you know what? I got to give him credit. Sort of funny how he -- he punk'd us. Anyway, Mary Frances, thank you.

BRAGIEL: Thank you, Greta.

VAN SUSTEREN: Now, Ric Mims, Sergeant Peterson's former friend and who stayed in the Peterson home with Drew in the days after Stacy was reported missing, joins us in Chicago. Ric, I don't know if you just saw that. It was sort of interesting, the horn honking on Drew's car, an interesting tough. But anyway, let's talk about these guns. When did you stay at Drew Peterson's home?

RIC MIMS, FORMER FRIEND OF DREW PETERSON: Shortly after Stacy disappeared. I showed up there I believe it was the Tuesday, and I stayed until right at the 1st.

VAN SUSTEREN: All right. So -- so she disappeared Sunday, the 28th, 29th. So you arrived on the 30th. Did you ever see -- did Drew ever show you these guns? And of course, at the time, he was a police officer, you know, an active police officer. Did you see any guns in his home?

MIMS: Prior to Stacy disappearing a few years ago, he was showing me his gun collection and he had showed me the weapons, you know?

VAN SUSTEREN: All right. The one in question, which is the AR-15, apparently, at least the allegation is, is that it has been -- that it is too -- the barrel is too short, that it might have -- has it been altered, do you know?

MIMS: I don't think so. I think that he purchased it that way. He's not a gunsmith. He's just a gun collector, so...

VAN SUSTEREN: It -- and...

MIMS: I don't think he would personally alter a gun to make it illegal. I think he purchased it that way.

VAN SUSTEREN: All right. And the allegation, it's three eighths of an inch too short. At one time, it had a suppressor on the end of it. Did you ever see the suppressor on the end of that gun?

MIMS: I can't remember if it was on there or not when he showed me. Like I said, it was a few years ago. It was when he first moved into his house on Pheasant Chase (ph) there.

VAN SUSTEREN: Have you talked to Drew since you left his home?

MIMS: No. No, I haven't. I haven't had any contact with him.

VAN SUSTEREN: How come?

MIMS: I haven't had any reason to. I don't believe his story. I don't believe his alibis. He told me that Sharon next door was a liar, which I don't believe. So I made my own conclusions, and based on what the state police and Sharon and everybody that is close to the story has revealed to me, is that, I mean, he's guilty.

VAN SUSTEREN: He -- one of the allegations, Ric, was that a relative of his helped to move something out of that house. And we've tried to find that relative. Do you know where that relative is? He lives a couple blocks away.

MIMS: No, I haven't heard anything other than when the news story broke originally, that he was in the hospital for, I guess, trying to commit suicide right when -- about the same time Stacy disappeared. And I really don't know much about, other than what I've heard, you know, through the media.

VAN SUSTEREN: Ric, thank you.

MIMS: All right. Thanks, Greta.

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