The medical examiner ruled that Cooperhouse, 48, died of carbon monoxide poisoning and found no evidence of foul play.
The manner of death was listed as "undetermined" because the medical examiner could not tell if the death was a suicide or an accident. Investigating police officers have closed the case, calling it suicide.
But Cooperhouse's relatives and friends don't buy it. They insist he was murdered. And they think they know why.
Friends say that for years Cooperhouse dated teen-age girls. Some were underage. Some were students.
And those amorous pursuits - apparently well-known among students but a secret to school administrators and other teachers - finally caught up with him, friends believe.
They theorize he was murdered by an angry parent of one of his conquests.
Certainly, many students apparently knew about the affair Cooperhouse had been having with a 17-year-old student at the time he died.
"A lot of people knew," said Melissa Kaplan, a junior. "There were rumors. Some of it was false. But some of it was true."
Mike Smith, who called Cooperhouse one of his favorite teachers, said, "My whole class knew about this before he died. A lot of parents knew, too."
School officials think Cooperhouse killed himself because he learned that School District officials were beginning to investigate his latest affair. "There was no evidence of foul play, and so there's no suspicion," said Capt. Linda MacLachlin, a police spokeswoman.
But the fire scene left plenty of reasons to suspect foul play, say friends and relatives, who have hired a lawyer to press for a formal investigation.
"The cops said he may have set fire to himself with gasoline or some other liquid. But the cops said there was no can found in the garage or the car," said one close friend, Madelyne Bradley.
"Also, he was strapped in his seat belt and his bags for skiing were next to the door. He had been bragging about going skiing and he was looking for a new house in Bucks County," she added.
"He had all these plans. People who want to kill themselves don't make these kinds of plans."
Cooperhouse's sister agrees. "I believe my brother was murdered," said Eve Greenberg. "He did not commit suicide. He had everything to live for."
Greenberg, of Pemberton, N.J., last saw her brother Dec. 15, a day after she learned her husband had been diagnosed with cancer, a disease which also had killed their father.
"Knowing I had to face this and knowing what my mom had to deal with with my father's death, he wouldn't do it," his sister said.
Even more fundamentally, says the family's lawyer, John Beggin, is this: Why can't the fire marshall say how the fire started?
"It didn't make sense to me," he said.
COOPERHOUSE, who had taught biology at Washington for 16 years, was adored by students.
He was one of them, they say, and he was always there - Blue and Gold night, proms, dances, football games. He doubled as debate coach and junior class sponsor.
"He was a very nice person, gentle, quiet, private, very well-liked by the kids," said Dottie Washington, the school disciplinarian.
Cooperhouse - well-known around school for his exotic collection of birds, fish, turtles and snakes - was also well-known around some circles for his dating habits.
His adult friends knew he had dated a number of young girls - some underage and some his students - over the years. Many students at least knew of the affair he was having at the time he died.
"He knew I didn't approve," said Richie, Cooperhouse's best friend, who asked that his last name not be used.
Richie, who met some of of Cooperhouse's girlfriends over the years, said he had warned the teacher it would lead to trouble. "I remember saying one day, 'You're going to get caught, worse, lose your job or run into a p----- -off father,' " Richie said. "He just felt he would not get caught."
That happened the week Cooperhouse died.
On the night before his death, Cooperhouse learned that an investigation was about to begin into a report that he had been seeing a 17-year-old student.
George Washington High Principal Harry Gutelius, a longtime friend of Cooperhouse and a pallbearer at his funeral, said the girl, a senior at George Washington, had told a school official about the affair before the Christmas break. The official reported the allegation when classes resumed the week of Jan. 4.
On Jan. 7, Gutelius told the girl's mother that he intended to formally notify Cooperhouse of the investigation the next day. He agreed to delay an official notice until Jan. 11 after the mother said she needed time to get help for her daughter.
That night - his last - Cooperhouse played poker with five friends, just as he had most weeks for 20 years.
He seemed fine, Richie said. He got up and washed the dishes at one point and talked about going skiing the next day.
The game ended around 11:30 p.m. and "Neil seemed absolutely normal, absolutely perfect," Richie said.
Some time after the game ended, school officials said, Cooperhouse's teen-age girlfriend called him to tell him that Gutelius knew of the affair.
On Friday morning, Cooperhouse didn't show up at school. Then, school officials heard about the fire at his house.
Later, the girl told school officials that Cooperhouse had become distraught during their phone conversation the night before. She said he talked about killing himself.
Cooperhouse "was a really great teacher," said George Pettit, a junior. "Most of my friends said he was one of the best."
That's why even in death, students remain very protective of him.
Mary Branigan, the school's union representative, denied an investigation was even underway and said talk about an affair was just that - talk.
Gutelius, principal for the last 12 years, said he had no prior knowledge of the affair or of any others Cooperhouse supposedly had with students. The school's parents organization declined comment.
Gutelius, and fire and police officials, are convinced that Cooperhouse was distraught over the embarrassment, possible firing and possible criminal charges facing him.
"Appearances were important to him," Gutelius said. "The most important thing to Neil was his job and his status here. He was the only full-time who was an alumnus here, and he had a very high perch and he would have fallen a long way."If I hadn't been pursuing this, he wouldn't have killed himself," Gutelius said. "But you have to do what you have to do."
MANY PEOPLE who knew Cooperhouse cannot believe he would kill himself under any circumstances.
Since initial Daily News reports of his death in January, friends, colleagues and former students have peppered the newspaper with e-mail, phone calls and letters protesting any notion he committed suicide.Denny Horn, a close friend, cited questions surrounding Cooperhouse's death.
"His hands were gently resting in his lap as if he wasn't conscious during the raging fire," Horn said. "Also, many prized animals perished in the fire. The detective in charge does not seem at all interested in pursuing anything but the suicide theory. We will adamantly pursue this."
EVEN THOUGH he dated students and other young girls over the years, the relationships were consensual, his friends said. And there was no record of any parental complaints about him.
Even so, friends and family believe Cooperhouse died at the hands of an angry person who somehow rendered him unconscious with an untraceable drug, put him in the car, fastened the seat belt, set him on fire and left.
Their suspicions center on a parent or some other relative who had discovered his taste in females. "Certainly, there is concern that any number of people might have found this offensive," said Beggin, the attorney hired to investigate Cooperhouse's death. "There is reason to believe that somebody might want to hurt this man."
He said his investigator theorizes that someone forced Cooperhouse into the car, bound him with rope, let the car run, then burned him to cover their tracks.
The shot glasses rested on the kitchen table where each player had left them after the card game the night before. Each of their last poker hands lay face down just inches away.
A box with bills and important papers, which friends and family say Cooperhouse often left out in the open, sat in the middle of the kitchen table.
In the corner of the table, where no one could miss it, lay Cooperhouse's hand-written will and a piece of paper with the names and phone numbers of four of his closest friends.
And though friends say the will was always out and lying around, fire officials don't believe it was on the table during the card game, supporting their suicide theory.
Assistant Fire Marshall John Dougherty says there's still a mystery - the timing between the carbon monoxide poisoning and the start of the fire.
But while there are no definitive answers to why the fire started, fire officials believe strongly that the case was a suicide. "I called the fire incendiary, but I have no reason to feel someone else did it," Dougherty said. "Homicide was not brought in initially because there was no suspicion that it was a homicide."
Cooperhouse, they theorize, got into his car around the time he would for school, turned on the motor and let it run as he held a lit candle or some other flame that would ignite his body after a certain period of time. He probably did not anticipate the fire would burn his house too, killing his prized animals, they said.
The carbon monoxide Cooperhouse inhaled sent him into a deep sleep and then into unconsciousness.
If Cooperhouse were unconscious but still breathing at the time the fire started, Dougherty said he wouldn't have felt the fire. But Richie can't believe Cooperhouse would risk his prized animals - or take his life the way police believe he did.
"Anyone is capable of taking their own life," he said. "It's just that the method seems bizarre. I just can't believe he would torch himself."
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