Driven To Extremes

In August 2000, Dennis and Mary Hill lost their 13-year-old daughter, Amy, in a tragic car accident.

"I just see how hollow my life is now," says Dennis. "And I never thought I would experience that in my lifetime."

"I believe the reason I was put on this Earth was to have Amy," says Mary.

Before the accident, the Hills appeared to be living the extremely good life outside Orlando, Fla. They owned a successful marketing business, lived in a stately home, and their daughters, Amy and Kaitlin, were excelling in and out of school.

On Aug. 7, 2000, Mary and Dennis went to pick their daughter, Amy, up from her first day of eighth grade. With her were best friends Carrie Brown and Zak Rockwell. The three were inseparable.

On the way home, Dennis told Mary he needed to make a stop. Mary drove off with the three kids in the back seat. Everything would change during the next few minutes. Correspondent Peter Van Sant reports on how this seven-mile trip home from school ended in tragedy. This broadcast last aired on March 19, 2005.

Although Mary says she was pumping the brakes, the car kept accelerating: "I have been a good driver my whole life. But I could not stop that car. My last thought was 'Why won't you stop?'"

Investigators believe that Mary's BMW was traveling at 73 miles an hour when it slammed into a tree. The point of impact left a two-foot divot, right next to where Amy was sitting. Her best friend, Carrie, was in the middle with Zak, the farthest from the point of impact. Mary, who was not wearing her seatbelt, was thrown 24 feet out the side window.

"I woke up. I thought I was on fire," says Mary. "The heat was immense."

"It was just the most horrible experience I could ever imagine," says Dennis, one of the first people to arrive on the scene. He immediately went to the back seat and tried to feel the pulse of his daughter. "I thought, 'Oh please, I'm not doing this right. I'm doing something wrong. She's still alive and I just can't tell.'"

Dennis then checked for Carrie's pulse and felt nothing. Zak was unconscious but breathing.

"I just could not believe this was happening. I wanted to say, 'OK, guys. Cut. Let's start this over. Let's play this scene over,' because this is not the way I want it to be," says Dennis. "Just five minutes before, they were alive. Life was good. And then, five minutes later, your life changes like you never thought that it could."

A 48 Hours animation shows how police believe the accident happened. After Mary made a left turn, her car began to accelerate rapidly. As it started to drift into the oncoming traffic lane, it fishtailed and began a sideways slide.

Police estimated the car was traveling 73 miles an hour when it left the road. After it hit the tree, the car traveled 20 feet to its resting spot on the other side of the tree.

Zak's dad, Keith Rockwell, assumed his son was taking the bus home that day, until police showed up at his door. He rushed to the hospital to find his 13-year-old son alive, but unconscious. "They basically said he was in a coma, and that the longer he was in, the worse it would be," recalls Rockwell.

Carrie's mother, Rita Brown, was running errands when a friend called her cell phone and insisted on meeting her. "I collapsed. I couldn't believe it. Not my baby. Not my baby," says Brown.

But once some of the shock started to wear off, the questions started. Was this tragic crash really accidental?

For Mary, the guilt of driving the car that killed the two girls, and left the third child in a coma, was unbearable: "Why couldn't I have died? I lived a life, you know? I cannot accept something that I don't have a reason for. I am angry and everyone is angry, I know, at me."

Rockwell was terrified, but considered himself strangely lucky that his son was alive: "As a single dad, it's just me and him, and he's No. 1."

For four days, Zak's loved ones kept a bedside vigil until he woke up. Although Zak has no memory of the accident, he was on the road to recovery. But some wounds would never heal. "I lost a lifelong friend, partner," says Zak. "I lost a lot of things."

"I felt sorrow and anger. I was mad," says Brown, a world-renowned Olympic gymnastic coach. "I was just mad that Carrie was gone and it wasn't fair. Why my baby? Why is she gone? Why did this happen?"

But Brown's grief soon turned to anger when she learned the details of what one witness saw just before the crash.

Jimmy Arthur was on his way home from work when he saw Hill's BMW. "She almost sideswiped me. I mean, she just came out from no place," says Arthur, who was attempting to change lanes when he first encountered Mary's BMW. "I didn't feel like there was any mechanical problem. It just seemed like she was upset or angry or just in a very, very big hurry."

She was in such a hurry, adds Arthur, that she overshot a red light: "She put the car in reverse and quickly backed up, burning the tires and I thought she was going to hit the front of the van at that time. Once the light changed, she floored it, and the tires were screaming and she took off."

Arthur says he watched as Mary then lost control of her car and wrapped it around the tree. And his eyewitness account would become crucial to investigators as details about Mary began to surface.

"In a speeding car, I feel unsafe. And I usually did in Mrs. Hill's car," says Zak. "She always seemed like she was depressed."

In fact, Mary had been receiving treatment for depression. And in the days leading up to the accident, investigators learned Mary had been behaving strangely, including making a bizarre phone call to Brown.

"She says, 'Well, I'm going in Monday for shock treatment' and I said, 'Shock treatment for what?' And she goes, 'Well, I haven't been doing well and they thought they might try that,'" recalls Brown, who wasn't the only witness to Mary's unraveling.

Vicki Hartzell encountered Mary one afternoon in her driveway. "She was weaving and she was very unsteady on her feet," recalls Hartzell.

Hartzell says she told her two daughters that they weren't allowed to ride in the car with Mary anymore. "I felt there was something wrong with her," she says.

But a blood test after the crash revealed that Mary wasn't using drugs or alcohol. So, did Mary lose control of her car or her emotions?

On the advice of her attorneys, Mary did not speak to the victims' families. "To tell you the truth, there aren't any words in the English language that could ever express my sorrow for what happened," says Mary. "'I'm sorry what happened to your daughter.' I can't face that woman and say that to her. Everything I have known is gone for me -- my work, my life, my mobility, my spirit. I don't know what else to be taken. I don't know how it could be any worse." Eight months after the accident, when Mary was at rock bottom, prosecutors charged Hill with two counts of vehicular homicide and manslaughter. The charge carried a prison sentence of up to 30 years.

"I never expected it," says Mary. "Not for the most fleeting second could I think that someone would think that I would do something like that intentionally."

Now, Mary and Dennis Hill are fighting back. "We've endured our share, and it's time to turn the tables now. I believe that we're gonna be ready," says Dennis, who has hired high-priced defense attorney Gerald Boyle, best known for defending killer Jeffrey Dahmer, to prove his wife did not intentionally kill their daughter and her friend.

"Mary was an exceptional driver," says Dennis. "I never quite understood how this could possibly happen."

But defense experts think they have an answer. After examining the BMW, they believe a fault in the BMW's cruise control caused the car to speed up on its own.

"Once the investigators were able to say 'Hey there's a problem with the cruise control here. The throttle linkage,'" says Dennis. "Well then, pieces of the puzzle started to go together."

BMW owner Larry Gustafson has never met Mary, but he knows what it's like to have a car suddenly race off.

"The first time it happened to me, I had no idea what was going on," says Gustafson. "It went from 35 to 40 miles an hour to almost 60 miles an hour, just that quick."

Gustafson claims his mechanic fixed the problem on his used BMW by replacing an electrical circuit. But Carrie's mother isn't buying it.

"Mary Hill needs to be held accountable for her actions. And if that includes going to jail, then so be it. The judge and jury will decide," says Brown, who believes that Mary is to blame for Carrie's death.

Both mothers are unable to share their grief over the loss of their daughters, Amy and Carrie, for the battle lines have been drawn.

Mary, charged with vehicular homicide and manslaughter, has become a recluse.

"For over two years, I wouldn't leave this home," she says.

Making things difficult were the rumors flying furiously through their posh Florida community, rumors that Mary had a history of depression, drug use, and dangerous driving.

Sworn statements by Deane David, the Hills' former nanny, fueled those rumors. "I know that something like this was going to happen," says David. "She was a horrible mother. … That was my worst fear, was her in the car with them."

"She has accused me of horrible things," says Mary of David, who worked for the Hills for less than year, and left after a falling out over pay six months before the accident.

David's most scathing allegation was that Mary abused cocaine. "Two weeks into the job, I found out that Mary had a cocaine addiction," says David. "Her purse had fallen off the counter, and in that, a compact had fallen out with powder on the mirror and a razor blade."

But Mary denies these allegations: "I have tried it. I will not say I haven't tried it. But no, I never had an addiction. I don't think trying it once makes you an addict." Two and a half years after the accident, the trial has been delayed three times, and the pressure on Mary and Dennis Hill has reached the breaking point.

New charges have been filed in court that takes this case from the tragic to the bizarre. Now, Mary wants a divorce, claiming that Dennis is violent and sexually abusive. And Dennis has counter-attacked with allegations that Mary has a history of drug abuse and alcoholism.

The battle plans are piling up in what has become the War of the Hills. "And the War of the Hills is almost as dramatic as the War of the Roses," says Dennis, who believes Mary should not have been charged. "If they would've followed us around and filmed this thing, it would've made a heck of a movie."

In spite of Dennis' public support, Mary has thrown him out and even got a restraining order against him. "Dennis was into physical pain for sexual gratification. Both giving and receiving," says Mary. "It got to be far too much."

"That's absolutely not true. In 25 years, I never hit that woman," says Dennis, who denies sexually abusing his wife. "Absolutely not."

But Mary says she's afraid of Dennis: "He admitted openly in court, after I filed the injunction to keep him away from me, he was going to slash my face to pieces and see me disappear."

"I got so mad," explains Dennis. "I said 'You know, Mary, I'd like to get a two by four and just come and smash your face in.' Of course, I regret saying that."

But there's another casualty in the War of the Hills: their 13-year-old daughter, Kaitlin, who claims that her mother once told her that she wished Kaitlin had died in the accident instead of Amy.

"That is true. I'm not perfect, and yes, I did. And I apologized," says Mary. "And I apologize to this day. But I was so consumed with the loss of Amy."

With Mary facing homicide charges and Dennis accused of domestic violence, both parents lost custody of Kaitlin, who was sent to live with her older half-sister, Jennifer.

"I've lost two daughters. I can't accept that, I'll never accept it," says Dennis. "I'll fight until they put me in the ground."

As Mary's trial date finally nears, she has hired Tim Berry to represent her.

The trial Mary Hill has waited three and a half years for was about to begin. In August 2000, Hill's BMW slammed into a tree, killing her daughter, Amy, and Amy's best friend, Carrie Brown. "I wish I could change everything that happened that day," says Mary.

If Mary is found guilty, she faces the possibility of up to 30 years in prison. "I'll die in prison," says Mary. "This is a fight for my life."

Attorney Tim Berry, who will lead Mary's defense team, claims a malfunctioning cruise control made Mary's BMW speed out of control. He's not sure, however, if he'll put Mary on the stand.

An all-female jury was to determine Mary's fate. They must decide if she's guilty of vehicular homicide, manslaughter and negligence for Zak Rockwell's injuries.

In his opening statement, Prosecutor Bart Schneider says it's clear Mary's reckless driving killed Amy and Carrie. But Berry tells the jury the real culprit in this tragedy is the car itself. And despite Mary's well-publicized record of mental and marital problems, Berry claims his client is not suicidal or homicidal.

The prosecution, however, uses eyewitness Jimmy Arthur to prove their theory that Mary was driving out of control.

With emotions running high, Dennis Hill is called to the stand, and the lead prosecutor, Pat Whitaker, tries to use Dennis to undermine Mary's claim that the BMW was defective. When asked about the BMW, Dennis testifies that he had no problems with the BMW that day. The jury hears nothing from Dennis about his bitter separation from Mary, or allegations of physical abuse. And Dennis tells the jury that Mary was in a very good mood just hours before the accident.

Suffering from a stomach ailment, Mary was forced to leave the courtroom. During her recovery, the jurors take a field trip to the site of the crash, to see firsthand where Amy and Carrie died.

The defense team relies on a British electrical engineer to convince the jury that the accident wasn't Mary's fault, but rather a fault in her BMW. The engineer, Dr. Antony Anderson, testifies that the reason for the accident was "a sudden acceleration event" caused by what he claims is "a rogue electrical signal."

"A rogue signal can come in and give a false command … which can affect these very sensitive electronic circuits within the cruise control," says Anderson, who believes this false command could have switched on the BMW's cruise control, triggered the accelerator and caused the car to speed up on its own.

But the prosecution's BMW expert, Mark Yeldham, twice tested Mary's BMW and found "no faults stored in the cruise control system."

Yeldham, who works for BMW, admits the company receives dozens of sudden acceleration complaints every year. But of those 50 complaints each year, Yeldham says most involve driver error.

In a final move to bolster their runaway car argument, the defense calls two drivers who claim their BMWs had also experienced sudden acceleration.

And on the last day of the trial, after three and a half years of silence, Mary is called to take the stand. Incredibly, it was the first time Brown and prosecutors have heard from Mary about the crash.

"It picked up speed. It started going faster. I released the brake and applied it again," says Mary. "The car started to go out of the lane, it was fishtailing. Everything was very quiet, and I remember looking down at the dash, and said 'Why won't you stop?'"

After five days of testimony, it was up to the jury to decide Mary's fate.
If found guilty, Mary could spend the next 30 years behind bars. After just five hours, the wait was over.

The jury found Mary guilty on all counts, a dramatic rejection of her claim that her BMW had sped out of control on its own, killing Amy and Carrie, and causing brain damage to their friend, Zak Rockwell.

"I prayed and hoped that justice would come, and it came today," said Carrie's mother, Rita Brown.

Mary will remain free on bond until sentencing, but she is ordered to hand over her driver's license. As reporters mob her, Mary is too distraught to talk.

But Heather and Julie Hill, Dennis' daughters from his first marriage, have plenty to say. They contacted 48 Hours after the trial, with explosive allegations the jury never heard.

They say they know what it's like to be in the back seat of a speeding car driven by Mary. "She got mad at my dad and she tore down the highway going like 90 miles an hour. I remember I was so scared in the back seat," says Julie.

"They're angry at me over Amy's death. I'm not their mother; I'm their stepmother," says Mary. "Truthfully, if I go to jail, let's face it, it will help their father considerably with the divorce."

And it's jail time that Brown pleads for at Mary's sentencing: "Carrie will not go off to college. I will not be able to spoil her children. I will not be able to take care of them when she's on vacation with her husband, the husband she never met."

For the first time since the accident, Mary utters the words Brown has waited so long to hear: "The words 'I'm sorry' can never convey to her how I feel. I do apologize to the parents and to the families and to the friends and to everyone that knew Carrie and Amy and Zack."

"I felt like she meant it, but it's too little too late, I guess," adds Zak.

The judge then surprises everyone by ordering Mary to jail until he decides on her sentence. Even her estranged husband, Dennis, finds the sight of her in handcuffs unbearable.

"It's probably one of the worst moments I've ever gone through in my life. It hurt a lot, it really did," says Dennis. "I just think that she will just will herself to die and she'll just die in jail, and I don't know if I can really handle that."

More than three months later, a visibly shaking Mary Hill, now being treated for depression and alcohol and drug addiction, is back in court to hear the judge's decision. She was sentenced to serve 15 years in the Department of Corrections in Florida.

Mary received the sentence with some advice from Judge O.H. Eaton: "Mary Hill, I don't know what you're gonna go with your life. You're going to have to make a lot of adjustments."

Mary once had it all: a successful business, a mansion where she raised a loving family, and a world of possibilities. But now, a prison will be the only world Mary will know until she's almost 70.

But will the tragedy ever truly be over for any of the survivors? Mary and Dennis are getting a divorce.

Kaitlin is still in custody of her older sister, and must deal with the haunting memory of her mother in shackles. And Rita Brown can only dream of what her daughter, Carrie, might have become.

Despite their testimony, the judge denied Hill's request for a new trial. She's filing an appeal.

After serving 10 months in prison, Mary Hill was released on a $50,000 bond pending the outcome of her appeal.