Overview of Unmasking the Monster
NBC News’ Dateline episode follows the decades-long investigation into the brutal 1989 rape of Dana Beatty in Cincinnati, Ohio, and the daughter who ultimately helped solve it. What began as a cold case with no clear suspect was revived through modern DNA genealogy and persistent detective work, revealing a shocking answer: the attacker was Fred Tanzer, a trusted figure in Dana’s social circle and the ex-husband of her best friend. Because the statute of limitations had expired, Tanzer could not be prosecuted for rape, but federal investigators built a new case and convicted him of lying to the FBI.
What Happened in 1989
The attack
- Dana Beatty, then 29 and working a successful sales career at IBM, returned home one August day in 1989 to find an intruder waiting in her condo.
- The attacker:
- wore black clothing and a full mask
- carried a butcher knife
- restrained her with tape and pantyhose
- assaulted her repeatedly for more than five hours
Crime scene details
- He left a handwritten warning: “No police, I’ll be back, Miss IBM.”
- Police recovered:
- semen evidence
- fingerprints
- the knife
- tape and other physical evidence
- clues from Dana’s answering machine, which became a key source of leads
The Investigation: Dead Ends and Suspects
Early focus
Investigators pursued several possible suspects, including:
- a police officer who had shown an obsessive interest in Dana
- former dates and acquaintances
- a doctor and a neighbor who matched parts of the description
- men whose voices appeared on Dana’s answering machine
Why the case stalled
- DNA testing in 1989 was too limited to solve the crime directly.
- Many suspects were eliminated through alibis, fingerprints, or DNA.
- The case went cold for years, leaving Dana in fear and constant hypervigilance.
The Daughter Who Reopened the Case
Andra Beatty’s role
- Dana’s daughter, Andra Beatty, grew up around the lingering fear and secrecy created by the assault.
- As an adult, Andra became deeply interested in true crime and cold cases.
- She emailed police after seeing a solved Cincinnati sexual assault case and wondering whether new methods might help her mother’s case.
Modern forensic breakthrough
- Detective Jeff Smallwood reopened the file and found the original evidence preserved.
- Using forensic genetic genealogy, investigators traced DNA to a short family line.
- The results pointed directly to Fred Tanzer.
The Shocking Identification
Who Fred Tanzer was
- Tanzer was:
- Dana’s best friend’s former husband
- a doctor
- someone Dana had known socially for years
- one of the voices on her old answering machine
- Dana initially ruled him out because she knew him personally and never suspected him.
A painful realization
- Investigators confronted Dana with the match, and she was stunned.
- The reveal reframed memories she had long carried: his behavior at social gatherings, his closeness to her circle, and the fact that he had once stayed in her home.
Legal Roadblocks
Why rape charges were impossible
- Ohio’s statute of limitations for rape had already expired.
- Prosecutors later discovered the law change did not revive this case.
- As a result, Tanzer could not be charged for the sexual assault itself.
What investigators did next
Since the rape charge was blocked, the FBI and federal prosecutors looked for another prosecutable offense:
- They interviewed Tanzer under the pretense of investigating a police-related complaint.
- Tanzer denied knowing Dana that day and denied any wrongdoing.
- Investigators believed he lied to federal agents.
Arrest, Plea, and Sentencing
The federal case
- Tanzer was arrested for lying to federal agents.
- He later pleaded guilty to three counts of making false statements.
The sentence
- In 2026, he received the maximum sentence of 15 years.
- Dana delivered a victim impact statement, but said the punishment still felt incomplete because he was never prosecuted for the rape itself.
The Wider Harm
Dawn Tanzer’s account
- Tanzer’s second wife, Dawn, told investigators that he had also drugged and sexually assaulted her during their marriage.
- She said he admitted to drugging her multiple times.
- The episode notes that Ohio’s marital rape exception left another legal barrier in place for years.
Main Takeaways
- Persistence matters: The case survived for 35+ years because Dana, Andra, and detectives refused to let it disappear.
- Genetic genealogy changed everything: Old evidence became powerful once modern DNA tools were applied.
- Justice can be partial: Tanzer was caught and imprisoned, but not for the rape due to legal time limits.
- The trauma lasted decades: Dana’s life, marriage, parenting, and sense of safety were permanently shaped by the attack.
- Advocacy remains important: The episode underscores the need to revisit statutes of limitations in sexual assault cases.
Notable Theme
The episode is ultimately about how a daughter helped give her mother back her story. Andra’s decision to push the case forward transformed a family burdened by fear into one that finally had answers, even if not the full justice Dana deserved.