The Lanny Horwitz murder
Lanny Horwitz was shot nine times in his Florida home on Sept. 30, 2011. There were two people in the house -- who pulled the trigger?
High school sweethearts Lanny Horwitz and Donna Carnevale, first and second from left, met in Buffalo, N,Y. Lanny's brother, Barry, far right, recalls many joyful memories in the years that followed, like this one at a costume party.
Donna Carnevale
According to Lanny's brother Barry, "Donna was a knockout. He [Lanny] didn't wanna date anybody else."
Young Lanny Horwitz set on success
In this photo, Lanny, 11, helps straighten his father's tie. Lanny's brother, Barry, left, told "48 Hours" that Lanny had his eyes set on success at a young age. By age 16, Lanny was selling real estate for his father, a successful Buffalo developer.
Dan Carnevale
Donna also came from a well- known family. Donna's father, Dan Carnevale, a Buffalo baseball hall of famer was the only man to ever play for, manage, and serve as general manager of the Buffalo Bisons.
Donna and Lanny wed
In 1967, Lanny and Donna married. They were both in their early 20s.
The Horwitz's luxe life
According to Lanny's brother, Barry, the couple had it all. "They're able to travel all over the world. He had sailboats. He had airplanes. Anything life could offer was there for them."
The Horwitz family
The couple's seemingly perfect life was made even more complete with the addition of their only child. Son Radley was born in 1974.
Building the Horwitz home
The family moved to Boca Raton, Fla., in 1977. In 1990, they move to the gated community of Admiral's Cove in Jupiter, Fla. In this photo, Lanny oversees construction in the home he would be murdered in years later.
The Horwitz's rocky relationship
Despite the couples' wealth, their lives soon became a soap opera: married in 1967, divorced in May 2001, remarried in September 2001, and then divorced again in June 2002.
Lanny Horwitz and Francine Tice
In the last few years of his brother's life, Barry Horwitz says Lanny was spending a lot of time with this woman, his business partner, Francine Tice. When asked if he sensed they were in love, Barry told "48 Hours" "They had just met, but they were holding hands. You know, kid stuff." Barry hadn't seen his brother looking so happy in 40 years.
Lanny, Donna and Radley Horwitz
Barry didn't know that Lanny had decided to give his relationship with Donna one last shot. By April 2011, Donna and Lanny had moved back in together -- still divorced -- along with their grown son Radley, a single dad.
Donna Horwitz a doting grandmother
Donna was a devoted grandmother to Radley's young daughter.
Lanny Horwitz murdered
The reunited family was short lived. On Sept. 30, 2011, Radley awoke to the sound of gunfire and his mother screaming. When he came downstairs, he discovered his father lying on the bathroom floor. He had been shot nine times.
Investigating Lanny Horwitz's murder
When authorities responded to the wealthy gated community of Admiral's Cove, they discovered the house undisturbed, except for the bloody bathroom where Lanny's body was found.
Radley Horwitz talks to police
Radley Horwitz is seen the morning of his father's murder. Detective Eric Frank of the Jupiter, Fla., Police Department described him as stoic but cooperative.
Police: Donna Horwitz refuses to answer questions
Detective Frank told "48 Hours" that Donna Horwitz refused to answer any questions. In this photo taken that morning, she is barely visible, sitting in the passenger seat of Radley's car. Her hand is covering her face.
Inside the Horwitz crime scene
CSI Investigator Tracie McClendon processed the scene. Here, she takes "48 Hours"' Peter Van Sant through the crime scene, indicating a bullet hole in a towel that was hanging on the shower door. She says this shows that Lanny was first shot while in the shower.
Inside the Horwitz crime scene
McClendon points to where a phone hung on the wall. Lanny Horwitz was found with the receiver by his head, and the cord pinned between his arms. McClendon believes Lanny was trying to call for help. When investigators checked phone records, they found that Lanny was unable to complete any calls.
Video: Inside the crime scene
Arsenal of weapons found
Investigators examined the Horwitz family's personal belongings. They discovered an arsenal of weapons: In addition to two revolvers used to murder Lanny, they found 24 other weapons ranging from handguns to assault rifles.
Ammunition found in Horwitz home
Investigators found thousands of rounds of ammunition in the house, stored in these military-style boxes.
Donna Horwitz's diary
Investigators discovered a day planner Donna used as a diary. The last entry, dated less than a month before Lanny's death, reads, "Lan went to Frans 5:20 Another day of lies and being 'Mr. Meanie'."
In the nine months leading up to Lanny's death, Donna writes the name Fran over 60 times, according to a count by "48 Hours."
Donna Horwitz arrested
Six days after Lanny's brutal murder, Donna was arrested for the crime. In this mug shot, she is unrecognizable from the dark haired, beautiful woman that stole Lanny's heart all those years ago.
Francine Tice and Lanny Horwitz
Prosecutors began to build the case against Donna, alleging that jealousy over Francine Tice was motive for murder. Tice adamantly denies that her relationship with Lanny was anything more than business partners and friends.
Text message
Prosecutors say communication between Francine and Lanny was constant, like this text message showing that that the night before the murder, Francine had planned to pick Lanny up at 8 a.m. for a business trip. The two never got to go. Lanny died an hour earlier.
The trial: Mother versus son
On Jan. 11, 2013, Donna Horwitz's murder trial began. In a shocking twist defense attorney, Grey Tesh, shown here, points the finger at Radley. Referring to Lanny's life insurance policy, Tesh claims that Radley had "had half a million reasons to kill him."
Radley Horwitz
Years earlier, Radley, a one-time licensed gun dealer, spent five months in prison for selling a handgun to a felon. Now a convicted felon himself, Radley had trouble finding work. Tesh was convinced that Radley was hard up enough for money to kill his father.
Blood at Horwitz crime scene
Tesh told the court it was possible that Radley had hired a hitman to do the job. To support this theory, Tesh pointed to unidentified DNA found under this smear of Lanny's blood on a gate at the home, possibly belonging to the real killer. Prosecutors argued that the DNA could have been left on the gate days or even weeks before the crime occurred.
More evidence at Horwitz home
Evidence supported various parts of Radley's testimony, including this orange earplug that was recovered at the home. Radley explained that as a light sleeper, he always slept with earplugs. When he heard gunfire, he removed them and stepped into a nightmare -- his father lying on the floor taking his last breaths.
Donna Horwitz learns her fate
The jury took just two hours to make their decision. Donna was convicted of first-degree murder with a firearm on Jan. 17, 2013. She was sentenced to life in prison with no chance for parole.
Remembering Lanny Horwitz
On what would have been Lanny's 68th birthday, family and friends gathered to share memories of the man they knew and release Lanny's ashes into the sea.
Remembering Lanny Horwitz
The group set sail off of the coast of Stuart, Fla., on the Island Princess cruise boat.
Remembering Lanny Horwitz
Francine Tice, second from left, attended the gathering and delivered a eulogy:
"... let us all never forget this most amazing, incredible human being who was always there for all of us. My dear friend, may you now please rest in peace."
Conviction overturned
Four years after being found guilty of killing Lanny Horwitz, Donna Horwitz won the right to have a new trial. An appellate court ruled that Donna's right to remain silent had been violated. During closing arguments, Prosecutor Aleathea McRoberts told the jury that Donna had refused to speak to police at the crime scene. The court ruled that the jury was not allowed to have heard this. Seen here at her second trial in May of 2017, Donna again looks unrecognizable.
A second conviction
This time, Donna was convicted of second, not first-degree murder. On Oct. 12, 2017, Donna was sentenced to 32 years with six years time served – at her age, virtually a life sentence. Donna could get out after serving 25 years, but she would be in her 90s. Her son Radley told "48 Hours," "I still can't help but feel a little bad for my mom."