by Chris Hansen, Dateline correspondent

I can remember as clear as the day it happened, that first donnybrook I had with my father over marijuana. It was a Saturday morning in the summer of 1979. I had just finished my sophomore year at Michigan State University and was working Monday through Friday hauling drywall, earning enough to pay half my tuition. It's still the most physically demanding job I've ever had.

It was about 11:00 in the morning. I was sitting at the kitchen counter, drinking the fresh-squeezed orange juice and eating the super-sized cheddar and bacon omelet my mother had just prepared. In walks my father from the garage after running his morning errands with my two younger sisters. I casually ask him "Hey, what's up?" The response was not good. As fate would have it, the night before as I was driving my dad's black Chevy Monte Carlo back from a concert with my pals, one of them mistakenly left his pot pipe on the passenger-side floor. This, of course, was found by my middle sister and given to my father, who was now throwing it at Mickey Lolich velocity at my head.

Thirty years have gone by since the summer of reduced-driving privileges. A lot has changed, yet much is the same. When I was in college, personal-use marijuana was akin to a traffic violation. Today, getting caught can have more serious consequences: a drug diversion program, community service, counseling and if you get caught while on probation, jail. The story of what happened to Rachel Hoffman is not meant to spur a debate over the de-criminalization of marijuana laws. There is a convincing argument to be made that it's a gateway drug and in the best-case scenario, daily use in colleges results in skipped classes and liberal arts degrees that take seven years to complete.

Yet, as the father of two teenagers, I am a realist. Kids will experiment. Rachel Hoffman had good and loving parents. She held a solid B average at Florida State University. There was little sign of trouble. Rachel, however, had developed a taste for high-quality weed and to afford it she sold it to her close friends. She was busted not once, but twice and this put her in a precarious position. Tallahassee Police offered her a deal: Go undercover as a drug informant, and you'll get out from under charges that could have landed you in prison.

Rachel agreed to the deal. What follows is a story of desperation. Rachel was desperate to get of trouble. The police were desperate to make a big bust, and the ultimate targets of the sting were desperate for cash as they decided to take advantage of a 23-year-old woman who had $13,000 in police money in her purse trying to buy cocaine, ecstasy and a gun. It was a recipe for disaster and it ended with Rachel shot to death on a rural Florida road. It was heartbreaking as a parent interviewing Rachel's mom and dad. But I was committed to doing it and showing it to all of you so something like this never happens again.

You can see the full story here: http://www.msnbc.msn.com/id/21134540/vp/28810295#28810295

And a web-exclusive video here: http://www.msnbc.msn.com/id/21134540/vp/28810294#28810294

You can check out my Newsvine profile here:
http://chris-hansen.newsvine.com/ 

Chris Hansen, Dateline correspondent

Every once in a while a story finds you. Such is the case with the hour-long investigation we'll bring you on Friday night, May 2.  

I think it's one of the most unique and interesting stories we've done this year and it came to us in an equally unique and interesting way. It was a tip from a Texas-based cameraman that got the ball rolling. In the past, Izzy Cardoza had done some work for NBC News and so he felt comfortable calling NBC after he says a so-called producer/reality show host didn't pay him for a project Izzy and his crew shot.

Izzy, as it turned out had kept all the tapes as collateral and when the producer/host never came up with a promised certified check, Izzy and his crew walked off the job with the tapes.

Guess who has the tapes now?

That's right, Dateline. And they not only make for compelling television, they allowed us to track down a group of contestants who say they were duped into believing they were going to appear worldwide on a reality show. The group was told that the winner would get $50,000 and the possibility of a big time modeling contract.

The host/producer was a fellow named Gemase Simmons.  He claimed to be a former supermodel, but as our investigation would reveal, that and so many other things he claimed couldn't be confirmed or just weren't true.

As you'll see, Simmons puts the contestants through the kind of grueling physical contests that have become reality show fare, but it's what was going on off-camera that was really bizarre.

We'll show you that, and also what happens when we go looking for Gemase Simmons to ask him what he was really up to.

'Reality Bites' aired on Friday, May 2. Click here to read Gemase Simmons' response after the broadcast.

By Chris Hansen, Dateline Correspondent

We'd been hearing complaints from senior citizens and government regulators across the country about the tactics some insurance salesmen are using to sell certain investments to retired folks. I'm a long ways off from retiring, but it's an important subject to me because my mom's close to that age and my aunts and uncles are already there. Given the turbulence we've seen on Wall Street, it seems like everyone is re-evaluating or repositioning their investments and would like to have their money in a safe place. And that's what a lot of salesmen are pitching these days.

The investments are called equity-indexed annuities. They may be appropriate for some, but not for everyone. Why are so many people trying to sell these to retired folks? Simple: that's where the money is. Seniors control more than $15 trillion in today's economy and for the salesmen, these annuities pay healthy commissions.

Dateline decided to use hidden cameras to find out what salesmen were really saying or not saying to seniors when peddling these investments. We attended some of those "free lunch" seminars put on for potential clients, classes where salesman are taught the tricks of the trade. We wired some houses in communities where a lot of retired people live, so we could see the one-on-one pitch play out in real time.

What we found in many cases was remarkable. Some salesmen are being trained to scare the elderly into buying certain investments. In our hidden camera homes, we saw that some agents were not disclosing how long the senior's money would be tied up, in some cases longer than the investor would live. We also saw some salesman not disclosing details about surrender penalties that would have to be paid if the senior had an emergency and had to access their money.

In order to carry out this investigation, though, we needed the help of some senior citizens who would invite salesmen over to hear the pitches. In Alabama, we met a 77-year-old semi-retired lawyer named Leon who fit the bill.

But we also needed help in Arizona. I had just seen my aunt Alice at a funeral in Chicago. She had come up from Arizona, where she lives part of the year. We had a nice chat and I expressed my condolences for her husband, my uncle Charlie, who had also recently passed away.

A few weeks later I wondered if Alice might be the perfect choice to help us in our investigation. After consulting my mom, I reached out for Alice who ultimately agreed to be a part of our story. She was perfect because she was exactly the type of person some salesmen seek: retired, widowed and in possession of a retirement nest egg.

She asked the right questions and as you'll see in our story she presents herself pretty darn well on camera. Now if I can only get the rest of my family working on my stories.

Click here for the full story and video of 'Tricks of the Trade.'

Click here to read more of Chris Hansen's behind-the-scenes looks at his investigations.

By Chris Hansen, Dateline Correspondent

It's our twelfth "To Catch A Predator" investigation and this time we're set up in a 6,000- square foot home in Bowling Green, Kentucky. It's a town of about 50,000 people an hour north of Nashville, Tennessee.

Each one of these investigations has its own rhythm and Kentucky is no different. Within hours I am struck by the fact that fewer men are showing up at our hidden camera house than in past investigations.

Looking back I think this at least partially because the Kentucky Attorney General's office and the Kentucky Bureau of Investigation, along with local law enforcement, have been actively pursuing online predators in the past year.

Before Dateline's investigation in Bowling Green, the Attorney General's office with the help of the online watchdog group Perverted Justice had conducted two previous sting operations without us, making 20 arrests.

One of them was a 59-year old criminal justice instructor at an Ohio college who used to be an elementary school teacher. He had been chatting online about having sex with a decoy posing as a13-year-old girl before showing up to meet her at the undercover house.

Even after this earlier high-profile case, though, we still saw men in our investigation eager to meet a young teen home alone for sex. As you will see, seven men show up over three and a half days and all seven are arrested after I talk to them and they leave the house.

You'll see in Kentucky that we employ the same online decoy, Casey, who we used in New Jersey. She is just as effective in this latest investigation as she was before talking to the men in person.

You'll see the grooming process in real time.

Also in Kentucky we see a range of men show up, from a factory worker to a man who says he's a police detective and carries a gun.

Watch the heart-pounding moments when, as he leaves our hidden camera house, he refuses to follow orders from the arresting officers.

'To Catch a Predator' Kentucky airs Friday, Dec. 28.

Click here for more about the series.

By Chris Hansen, Dateline Correspondent

The fireman
Tonight we're back in Ocean County, N.J., for the second part of our "To Catch A Predator" investigation. Among the first men you'll meet here is a guy who uses new ruse to convince a 14-year-old girl named Jane to let him come over to her family's house and have sex. Jane is really a decoy from Perverted Justice.

In his online chat 42-year old Rick Burnham pretends to be a 21-year-old college student going by the screen name "uconnbluenwhite". Then he introduces "Jane" to his older friend "stevetakespix" who supposed to be a real cool guy who just happens to be interested in taking the virginity of a 14-year-old.

We think what he's trying to do is not scare off the young teen by giving his real age in the beginning of the chat. As you watch Burnham walk into our hidden camera house, he's just driven three hours from Connecticut. Watch as it appears he want to get right down to business. He chats with Casey, our decoy, for a bit and when she excuses herself to go to the next room, he's right behind her. As I walk out to talk to him, we almost bump into each other.

That's when I see something sticking out of his back pocket. When I ask him what it is, he says it's his cell phone. I know it's not a cell phone so I say: "No. The other back pocket." As you're about to see, the item he pulls out leaves little doubt about his intent. Burnham, by the way, is retired fire department captain who says he's now a freelance photographer.

Grooming technique
We're about to see another man who makes himself comfortable on the beach of our multi-million dollar home on the ocean. James Marcott, 32, doesn't seem one bit nervous as his sits down to talk to our decoy posing as a 13-year-old girl. Perhaps he has experience talking to teenagers.

In his on line chat he told the decoy that he had earlier met a 15-year-old girl online. Watch now as he tells Casey that not only did he met her, he also had sex with her. When I talk to Marcott, he changes his story, saying he never had sex with a 15-year-old. Why would someone say this online?

Experts tell us it's a common grooming technique used by potential predators. Almost as if to say: "It's ok. Other kids you age have already done this." But in this case it's going to be another lead to be followed up on by detectives with the Ocean County Prosecutors Office.

Everyday guys
Once again, we see just how many of the guys who surface in our investigations look like everyday guys who don't stand out of a crowd. If you live in Pennsylvania, you might have even purchased a car from one of our next visitors.

When we meet 39-year old Jeremy Keister he has a job selling luxury cars. Watch as Keister walks into our home. Something spooks him right away. He almost freezes. I think it may have been when Casey offered him some brownies that something clicked and he maybe realizes he's just walked into a "To Catch A Predator" investigation. All doubt is removed when he admits he knows exactly who I am. He even says: "It's nice to meet you."

Head first
You may have seen last week's preview to tonight's show, where we showed video of one of our visitors who went head first into the bar in the family room of our hidden camera house. People have been asking me about it all week. Tonight, you'll see the whole story.

The man I'm talking about is 37-year-old Kazuo Akustso. When we meet him he's a shirt-and-tie salesman at a major Manhattan department store. I have seen a lot during the three years we've been doing these investigations, but nothing quite like this. Kazuo walks in, chats with our decoy Casey, and then I walk out. What you don't see on camera is that the color literally drains from his face.

I can't be sure that he knew who I was or what he has just walked into, but he knows it's not good. He goes down on his knees, gets back up and then apparently faints, crashing head-first into the bar. A medic comes in to check him out. Later police say he's OK.

What were they thinking?
As we finish up in New Jersey, consider this: nearly half of the 28 men who surfaced in this investigation had seen one of our earlier investigations. What does that say to me? Some people have suggested that some of these guys want to get caught, perhaps maybe even want to be on our show. Possibly, but I still think most of these guys just really don't think it could happen to them.

Click here for the script to "To Catch a Predator" New Jersey

By Chris Hansen, Dateline Correspondent

By Chris Hansen, Dateline Correspondent

These posts are meant to coincide with the broadcast.

10:03 p.m.
One of the things you may notice tonight as you watch our 11th "To Catch A Predator" investigation is how much more interaction there is between the men and the young woman we've hired to be our onsite decoy. In past investigations the young woman or young man typically invites the potential predator in, chats for a few seconds, and then disappears.

Here in New Jersey, where we've set up in a multi-million dollar home on the beach, our decoy Casey is able to have much longer conversations with the men. This gives us a keen insight into what they plan on doing to a young teen. Usually we mostly rely on the men's online chats with Perverted Justice decoys and while that does give us a graphic look at these guy's intentions, it is really startling to see them engage in the grooming process in real-time.

At the start of each of these investigations I'm never sure what to expect from the onsite decoy. They are usually college students who happen to look younger than they are, who have an interest in the theatre, and see this as a chance to perform and do something worthwhile in the process. All of the ones we've used have been sharp kids and have done a great job for us. Here in New Jersey, though, you'll see tonight Casey's work is extraordinary.

10:12 p.m.
A few months ago, in our Flagler Beach, Fla., investigation, we tried something different: a second location on the beach. Here in New Jersey, thanks to all the hard work of Mitch Wagenberg and his crew, we just about perfected it. It gives us the option of having the decoy invite the guys into a different setting. I wasn't sure it would work out as well as it did. Would the men be nervous about being seen in public with a young girl? What if a beachcomber walked by and spooked him?

As you'll see, it posed no problem at all. Several of our visitors seemed very comfortable in the beach chair. The real challenge was getting good, quality audio on the beach without having the men see a microphone. It's another technological feat. The microphones were hidden in seashells.

10:32 p.m.
I know I have said this before, but each time we do another "To Catch a Predator" investigation, I keep wondering if it's going to be the one where no one shows up. After all, this one is our 11th. We've conducted them in 8 different states now and 286 men have surfaced in the investigation over three years; 256 have been arrested and, as of this writing, 117 men have either pleaded guilty or been found guilty after a trial. You'd think word would get out -- and I suppose it has -- but here on the Jersey shore men are practically lined up at our door.

Many of them -- perhaps a third to a half -- know exactly what they've walked into as soon as they see me. In a few minutes you'll meet Michael Lubrano. He's 25 and comes to our house to meet a girl who told him she was 14. Here's another "To Catch a Predator first."

He brings marijuana and actually has Casey the decoy give it the smell test. Now listen to what he says when I walk out. He knows exactly who I am. In the back of my mind I'm thinking: How could a guy who "religiously" watches our show walk into one of our hidden camera houses? Listen to the compliment he gives me. For those of you who don't know, "Opie and Anthony" is a syndicated morning radio show.

10:44 p.m.
In this investigation we continue to see men from all walks of life and of all ages. Before the New Jersey operation is over we'll meet an engineer, a school bus driver, a former camp counselor, a retired fire fighter and, as you're about to see, a 33-year old Air Force mechanic named Ernest Timmons. He shows up after a sexually explicit conversation with a decoy posing as a 13-year-old girl. Watch how fast he moves after he comes into our house. I've never seen anything quite like this guy.

He's got his expensive digital camera in hand and ready to go as he tries to hustle Casey upstairs for some quick photos. There's a moment when our decoys tells him she wants to stay downstairs and talk first and that's when I sense he might be ready to take off. As I walk into the room and start to talk to him, he offers up his excuses: a big misunderstanding; a friend sent him.

While sweating profusely, he's sticking to his story. He tells me he's about to be deployed to Iraq. Apparently that's not going to be happening anymore.

By Chris Hansen, Dateline Correspondent

Our 11th computer predator investigation takes place in a multi-million dollar home on the beautiful shoreline of New Jersey. It's a picture perfect vacation spot for parents and children -- and for potential predators as well.

This particular investigation is full of firsts. We have had decoys in our hidden camera homes in previous operations greet and chat in person with our visitors, but this is the first time we were set up to capture such extensive interaction between the two. As you'll see, our onsite decoy Casey looks a lot younger than her 18 years, but don't be fooled.

She was exceptional when it came to making conversation with almost every one of the 28 men who came to our house. What makes this so revealing is that we not only see the potential predator engage in the grooming process in his online chat, we also see it in real time.

We have two separate places where the men can be greeted. One is inside the house in the family room and one is on the beach, with the roar of the ocean in the background. It's stunning to watch, as some of these men feel so comfortable sitting across from Casey in a beach chair explaining to her in person what they want to do to her sexually. A 53-year-old man named Eugene tells Casey, "You just relax. And I'll take care of everything, okay?" Then he says: "Just be your self. I'll just try to explain as I go. Tell me if you enjoy it." Of course he's not so explicit when I walk out.

In each of our recent investigations we've found men who have seen or heard about our "To Catch a Predator" shows and surprisingly, still show up to meet a young teen. I've gotten used to the fact that this will happen, but I have never seen anything like what happened in New Jersey.

There was actually one guy who came in and instantly recognized me. He told me that he was a religious "To Catch a Predator" viewer and that he never missed an episode. Before I could formulate my next question, he volunteered that he had heard me on a syndicated radio program and complimented me for doing a good job.

Once again we see men of all ages and from all walks of life, including a military man who seemed to be in a hurry. He comes running in with an expensive digital camera and tries to get our decoy to hustle upstairs.

Instead, he encounters me. Watch as his story changes and his situation goes from bad to worse in what is one of the most compelling "To Catch a Predator" shows we've ever put together.

"To Catch a Predator" airs on Wednesday, July 18 and Wednesday, July 25 at 10 p.m.

by Chris Hansen, Dateline correspondent

I just wanted to thank you all for the overwhelming response we've received after our latest investigations. As you know, in the past few weeks we have used some of the same enterprising hidden camera investigative techniques that we use in our "To Catch A Predator" series to expose other crimes and scams. Apparently many of you yourselves have been targeted by the types of thieves we recently highlighted.

First, in "To Catch A Con Man," we tracked down some of the people behind those e-mails most of us have received offering millions, if only we'd put up some of our own cash to help a stranger in a far away land access an account only the e-mail sender knows about. I posed as an investor and turned the tables on the con men by exposing and then confronting them.

On March 27th, we aired the first part of our investigation into identity theft and credit card fraud, "To Catch An Identity Thief." Tonight, we are showing you the second part. I don't know that we've ever infiltrated a crime syndicate the way we have in this story. We started by getting into chat rooms that are virtual thieves markets for stolen credit card information and identities. We formed "Hansen Discount Electronics" on the web and "CH Delivery" so we could track this crime and the people committing it from the United States through Europe and into West Africa.

I have heard from thousands of you who have been victimized by the kinds of crimes we have investigated. It got me thinking about other stories we could do using our investigative techniques and hidden cameras. I am sure you have some great ideas as well and I want to hear about them. This is a great forum for you to tell me about the things you think should be investigated. Perhaps you have even documented some of these concerns on video. I may want you to share that with us as well to get us started.

Thanks again and I look forward to hearing from you.

by Chris Hansen, Dateline correspondent

36 days ago, Cho Seung-Hui bought a gun at a shop in Roanoke, Virginia, a Glock 19.  I spoke with the owner of the Roanoke firearms Tusday afternoon, who told me that it was a "typical sale."

Cho, who was a resident alien, had three forms of ID, so he produced a Va. driver's license that established residency, a checkbook that matched, and his INS card. The gun shop did a background check, and Cho cleared the state police and federal computers. He was able to take the gun home with him after paying for it with a credit card.

The owner says Cho didn't make employees suspicious, that he seemed like a typical clean-cut college kid.

"I can't even begin to describe how I feel," says John, the owner. "One death would have been to many. This is horrible."

Gun sales in Virginia have been more than a sticking point with gun control advocates, not to mention New York City. NBC News analyst Michael Sheehan, who oversaw counterterrorism for the New York City Police Department, tells us many guns bought in Virginia end up on New York streets.

In the Virginia tech case, Cho purchased that 9mm legally. Earlier in February, he bought a 22-caliber handgun at a local Blacksburg, Virginia pawn shop.

If you're like most Americans, you know all too well how pervasive credit card fraud is. You might have been a victim yourself. A few years ago, I got a call from my bank asking if I had charged $24,000 dollars at a store in New Zealand? I most certainly had not, but I had bought my son something on a Web site that apparently was not secure and thieves were able to obtain and use my number.

In a groundbreaking investigation a year in the making, we'll take you into the thieves' markets on the Internet, where your stolen credit card numbers and identity information could be for sale at this very moment. Very seldom are we able to infiltrate a criminal syndicate the way we do in the case of our investigation into identity theft and credit card fraud.

We'll also show you who is involved in this multi-billion dollar fraud and we'll track the identity thieves all the way from the United States, through Europe and into West Africa. It was challenging, risky, but rewarding.

There are also a few light moments. As part of our investigation, we actually form an online electronics company and a delivery service so we can follow the trail of merchandise purchased with stolen credit and debit cards. We find that a number of items ordered are going to the same address and the man who lives there is re-shipping the items overseas, not knowing he's part of a criminal enterprise. In order to learn more about the operation, we invite him to the "offices" of "CH Delivery" to pick up some of the packages. It's actually an old warehouse-like building we've rigged with hidden cameras and microphones.

When the man comes in, I greet him and we start chatting. I ask him how he got into this business and he tells me it all started in an Internet chat room when he met  an attractive woman named Wendy who ultimately has become his business partner. He then leans over to me and gives me a warning about chatting online and what can happen if you get caught soliciting teenage girls for sex.

"Like you watch Dateline? A lot of these guys want to have sex with a 13-year-old and they show up and get caught."

He's talking about our "To Catch A Predator" investigations, but he has no idea who he's really talking to. Now, I'm not wearing a disguise-- just regular clothes a delivery company employee might wear: a fleece and a ball cap. He goes on to describe several scenes from our shows. Apparently he's a big fan.

As you'll see, he's about to find out that we're investigating a predator of a different sort and I am about to ask him to help us.

'To Catch an I.D. Thief' aired Dateline Tuesday, March 27, 8 p.m. on NBC. Click here for more on the investigation, including Web-exclusive videos, and video to the entire episode. Here are tips on protecting your identity.

Editor's note: Thank you for your responses, below. Please don't post anything you don't want published -- and again, don't forward us your spam, although tips are appreciated. We apologize if we can't publish all your comments, although we are reading them and appreciate the positive response. See you next week.

by Chris Hansen, Dateline correspondent

"My name is Mrs Maryam Ibrahim,...{I am} suffering from long time cancer of the breast...Before my late husband died  {he} deposited the sum of 20 million dollars ..20% of this money will be for your time and effort..."

If you're like me, you've likely received unsolicited e-mails offering you the chance of a lifetime. A financial windfall is out there and all you have to do is take advantage of a rare opportunity. They usually sound a little fishy. The pitch goes something like this --  a government official or someone with influence in an African nation has access to a fund containing millions of dollars. But, for some reason that person needs your help to get the money out of Africa and into another country. Oh, and by the way, you'll need to come up with $14,000 in processing fees and expenses. Once you wire the person this money…the multi-million dollar funds transfer can go through and you'll get a generous cut of the deal, perhaps $2 million dollars.

You might think that most people would simply hit the delete button, but our investigation reveals that perhaps tens of thousands of people each year take the bait and are taken for a ride, some losing hundreds of thousands of dollars. Usually these cases go uninvestigated, because federal authorities are busy with more pressing matters like counter-terrorism. We decided to take up the challenge and go after these scammers. As you'll see it's an investigation that takes halfway across the world and let's us turn the tables on the conmen.

Chris Hansen reports on 'To Catch a Con Man,' Dateline Tuesday, March 20, 8 p.m.

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