Transcribed verbatim from Hazel Thornton's summary found in "Hung Jury: The Diary of a Menendez Juror."
The Prosecution
Lyle and Erik Menendez murdered their parents for their inheritance, estimated at $14 million.
Jose Menendez, who had immigrated to the United States from Cuba as a young man, was a handsome, successful, charismatic Beverly Hills entertainment executive. He and his wife, Kitty, gave their sons, Lyle and Erik, every possible advantage: they lived in mansions, attended the best schools, drove their own sports cars, played tennis on private courts, and enjoyed exclusive country club memberships. Relatives admired and envied the Menendez family and considered it a privilege to be allowed to visit them. The boys were athletically gifted and, through the dedication of their parents, the help of extensive private coaching, and their own determination and hard work, both became nationally ranked tennis players.
Sadly, these boys were also spoiled, and one day they decided to kill their parents because they were greedy for their inheritance. First they drove to San Diego and bought shotguns (a clear sign of premeditation). Then, to establish an alibi, they made plans to meet a friend in Santa Monica two days later. On the appointed day, August 20, 1989, they burst in on their parents, who were watching TV in the family room, and shotgunned them to death.
Lyle and Erik disposed of the guns and drove to Santa Monica as planed - too late, unfortunately, to meet their friend. They drove home and called 911, sobbing hysterically, "Somebody shot our parents!" They were questioned by police, but, luckily for them, they were not considered suspects at that time. In fact, they were allowed access to the crime scene the next day and were able surreptitiously to retrieve incriminating evidence.
For the next seven months, the Menendez brothers successfully played the innocent, grieving sons. They even went so far as to speak at two memorial services for their parents. Further evidence of premeditation includes their inordinate interest in recovering their father's will from the family computer and their postcrime spending spree.
It was not until October 31, 1989, that Erik, the younger and weaker brother, confessed the crime to his therapist, Dr. L. Jerome Oziel. Dr. Oziel was bound by client-patient privilege not to divulge Erik's tale to anyone. However, when Lyle found out what Erik had done, he became very angry and threatened Dr. Oziel. Dr. Oziel told the story to his girlfriend, Judalon Smyth, to protect himself. It was she who, on March 5, 1990, directed the police to look at gun purchase records in San Diego, which resulted in the arrest of the Menendez brothers.
The Defense
Lyle and Erik Menendez, who had been terrorized all their lives by their parents, eventually killed them out of terror, believing at that moment that their lives were in imminent danger.
The Menendez family's fairy-tale life was not all it appeared to be. Jose Menendez may have been handsome, successful, and charismatic, but he was also very domineering, intimidating, and sadistic. Kitty Menendez was a jealous drug- and alcohol-dependent woman who worshipped her husband and resented her sons. Jose and Kitty abused Lyle and Erik in every way possible - mentally, emotionally, physically, and sexually. The boys were being molded in their father's image, and, when they didn't measure up, they were punished, belittled, and pitted against each other. The family was extremely private; the boys were systematically isolated and constantly warned not to discuss family problems with others.
The Menendez brothers enjoyed material privileges, but theirs were not lives of leisure. Although both were nationally ranked in tennis, their success was the result of a grueling practice schedule that precluded other interests and activities. Jose was constantly on hand to bark orders at them and to supervise a change in coaches who were not demanding enough or who began to get too close to the boys.
One day Erik, who was eighteen and still living at home, confessed to Lyle, who was twenty-one and just home for a visit, that their father was still sexually molesting him. Lyle confronted Jose and demanded that he stop. When Jose refused, Lyle did the one thing for which Jose had always sworn he would kill them - he threatened to tell someone outside the family. After a lifetime of abuse, the boys were hypervigilant and sensitive to their parents' every word and gesture. They now became convinced that their parents were planning to kill them to prevent anyone from finding out about the abuse, and they purchased shotguns in the event that they were forced to use them in self-defense.
On Sunday night, August 20, 1989, a series of arguments between the parents and the sons escalated to the point that the boys thought, "This is it! They're going to kill us now!" So they ran and got their guns, burst in on their parents, and, in sheer panic, emptied their shotguns.
Although the brothers felt sure someone must have heard the noise and called the police no one came, so they gathered all the shotgun shells they could find, got in the car, and drove away. They threw the guns down an embankment on Mulholland Drive, disposed of their bloody clothes at a gas station dumpster, tried (unsuccessfully) to buy movie tickets to use as an alibi, and tried (again unsuccessfully) to meet a friend in Santa Monica. Upon returning home they called 911 and, in genuine distress, reported the crime as if they had just discovered it.
Lyle and Erik spent the next several months pretending they did not know who had killed their parents, and genuinely grieving for them. They spent lots of money, but no more than was in keeping with their former lifestyle, for they had never been deprived of material things or spending cash. Neither of them knew much about computers, and their father had led both to believe that they had been written out of his will.
When Erik confessed his crime to Dr. Oziel on October 31, 1989, it was done to ease his guilt-ridden mind. However, the doctor did not do anything to help Erik; instead he basically blackmailed the brothers and breached their confidentiality by repeating their story to his girlfriend, Judalon Smyth. He kept her in the relationship against her will and controlled her by threatening to tell the Menendez brothers, whom she feared, that she knew all about them. When Judalon went to the police on March 5, 1990, it was not to report the Menendez brothers for killing their parents but to report Dr. Oziel for kidnapping and raping her.
On March 8, 1990, Lyle was arrested and sent to Los Angeles County Jail. Three days later, Erik voluntarily returned to California from a tennis tournament in Israel and was also arrested.