In 1989, a 29-year-old woman was attacked in her home by a man wearing a black full-body spandex suit, black gloves and a mask covering his face.
He wrapped thick white tape around her head and face, from the top of her forehead to the bottom of her nose, so she couldn’t see. He forced the woman into her bedroom and tied her to the bed frame with her own stockings.
He never spoke, except once, after she screamed, when he put a knife to her neck and said “shhh.”
He sexually assaulted her multiple times over five and a half hours. Between attacks, she heard him sitting in a rocking chair or listening to messages on her answering machine, leading investigators to wonder if he knew her and that his voice might be on the tape.
For 35 years, the case went unsolved and the woman lived in constant fear, always wondering whether her attacker would return. He left her a handwritten note in the newspaper threatening her:
“No police or I’m back, Mis IBM.”
The woman was working at IBM at the time. Then in January 2024, after Cincinnati police and the FBI re-examined the case, the woman learned who the attacker was.
He’s a doctor and her best friend’s ex-husband. In fact, his voice was on the answering machine tape.
“I’m sorry about your grandpa,” he said in a message about two months before the attack. “I’m thinking of you.”
Frederick Tanzer, now 67, could not be charged with rape because the statute of limitations had expired at the time.
But in 2024, when investigators questioned Tanzer at his Sycamore Township home about the 1989 attack, he lied and denied seeing or interacting with the woman that day.
Tanzer’s DNA was extracted from a Starbucks coffee cup he threw in the trash, and it did match the DNA at the scene.
Surveillance photo of Frederick Tanzer outside the Milford Department of Motor Vehicles office in April 2024.
Tanzer appeared in federal court in Dayton on Jan. 12 to be sentenced for making false statements to federal agents, a charge he pleaded guilty to last year. No prison sentence was imposed. U.S. District Judge Michael Newman will rule on Jan. 28.
There are many things to consider.
Tanzer himself admitted that he was the attacker. But he will be sentenced for making false statements. Prosecutors believe Tanzer is a serial rapist and are seeking the maximum possible prison sentence of 15 years.
Prosecutors noted that Tanzer was arrested at his Sycamore Township home in December 2024, and investigators found a gag, restraints and zip ties in his dresser.
Tanzer’s lawyers asked for a prison sentence of six to seven years.
“Unstable” and “Dangerous”
On January 12, at least 40 of the woman’s family and friends packed the courtroom. Among her supporters are her best friend, Tanzer’s ex-wife and her two children with Tanzer.
The two children, now adults, said their father was controlling and, according to prosecutors, they were afraid of him. The two had been estranged from him for years before his arrest.
One of them said in court documents that Tanzer was unstable, delusional, dangerous and had “no regard for human life or autonomy.”
Tanzer’s ex-wife, who divorced him in 2008, and his current wife have said Tanzer drugged them before having sex with them.
He has not yet been charged with those charges.
Woman describes life after attack
On January 12, the woman who was attacked in 1989 spoke at length in court.
She described how what happened at her apartment in Tusculum, Columbia, changed her life forever. She had been in therapy for decades and suffered from chronic anxiety, post-traumatic stress disorder, chronic insomnia, night terrors and panic attacks.
She said she couldn’t sleep in the dark. She damaged her teeth from prolonged clenching. Her husband learned to announce his presence when walking up the stairs or entering a room so he didn’t scare her and cause panic.
“I’m always on high alert,” she said.
Still, she said she would keep fighting and refused to let Tanzer win.
She noted that in the years after the attack, when Tanzer was still married to her best friend, she would sometimes see him socially.
Tanzer even attended her 1992 wedding.
“I remember him standing front and center,” she said.
She recalled wondering “why he was looking at me like that… like he was studying me.”
She remembered the last time she saw Tanzer, he was outside playing basketball with his children and others. Tanzer was angry because the kids were being shot more than he was, she recalled. So he “kicked a nearby puppy,” she said.
Tanzer made a statement in court
Tanzer’s appearance has changed since his arrest in late 2024. He has been imprisoned ever since. He no longer has dyed brown hair. It is now gray and cropped.
Frederick Tanzer.
In March 2025, his license to practice internal medicine in Ohio was permanently revoked. As part of his plea agreement, he allowed his medical license to expire in Kansas, Arizona, Colorado, Indiana and North Dakota.
He addressed the court on January 12.
“I am deeply sorry and remorseful for my past actions … and have been for a long time,” he began.
He then stood up and turned to where the woman he attacked in 1989 was sitting, close to his ex-wife and their children.
“I’m very sorry for what happened,” he said. “I wish I could explain it to you.”
“It doesn’t make any sense,” he said, adding that he hoped in his heart that the woman he attacked “won’t give up looking for me.”
“What I did was outrageous,” he said.
This article originally appeared in the Cincinnati Enquirer: Doctor exposed as predator who left chilling note after brutal attack
