True crime news logo
  • News
True crime news logo

The international true crime destination. Cases, documentaries, podcasts and travel routes.

© 2026 truecrime.news. All rights reserved.

Böse Spiele: 20.000 Akten enthüllen Justizirrtum im Fall Peggy

20,000 Documents Expose Justice Scandal in Peggy Case

Investigative journalist Marc Thiel analyzes police files to prove innocent man wrongly convicted

Author
Susanne Sperling
Published
May 8, 2026 at 12:17 AM

Quick Facts

LocationBirkenfeld, Unterfranken, Bayern — Verschwinden von Peggy Knobloch
AuthorMarc Thiel, investigative journalist since 1997
Scope352 pages based on over 20,000 case file pages
PublisherRiva (Random House), 2024, ISBN 978-3-7423-1325-3
MethodAnalysis of court records under German procedure, no speculation

A Justice Scandal Documented Word for Word

Twelve-year-old Peggy Knobloch disappeared on July 7, 1996, from Birkenfeld, Germany. Nearly five years later, her remains were discovered in a forest, and shortly after, Ulvi Kulac was sentenced to 8.5 years in prison. But 2023 brought the truth to light: Kulac was innocent.

Journalist Marc Thiel spent decades investigating this case. In his new book "Böse Spiele"—based on 20,000 pages of police files—he systematically documents how an innocent man was convicted. The book was published in 2024 and presented on German television in a program comparable to the American "Unsolved Mysteries." German prosecutors confirmed to ZDF that Thiel's book is based on authentic documents and contributes to clarifying the case.

Why does this work matter internationally? Because it reveals wrongful convictions and investigative errors that can happen anywhere—including in your own country.

Systematic Failures in the Investigation

When Peggy was found, police wasted no time. In 2004, Ulvi Kulac was convicted based on so-called "overwhelming evidence." Even Germany's Federal Court of Justice upheld the sentence.

But Thiel's analysis reveals what actually happened:

- Fiber evidence was not conclusive but was interpreted too broadly

- DNA traces were misinterpreted in the laboratory

- Interviews used suggestive questions that "produced" a confession

- Alternative leads were never properly investigated

This form of tunnel vision in police work had catastrophic consequences for Kulac. After five years and eight months, he was released on probation in 2010, but only 13 years later—in 2023—was he officially declared innocent. German prosecutor Bamberg concluded that "modern tracing technology excludes any connection to Kulac."

This raises uncomfortable questions about unsolved murder mysteries and who is actually responsible for Peggy's death.

Modern Technology and New Hope

The case is far from closed. In 2023, the Bavarian criminal police reopened the investigation using modern DNA sequencing—a technique that did not exist in the 1990s. Police leadership declared: "The case is not archived. New technology gives us hope."

Peggy's mother, Lieselotte, has publicly expressed her hope for justice. Thiel's book helps keep the case in the public eye and ensures that all the mistakes are not forgotten.

An Important Lesson in Justice

For anyone interested in true crime cases or working in the legal field, "Böse Spiele" is essential reading. The book is not sensational speculation without foundation—it is a methodical examination of what went wrong.

Thiel has written a work that calls on police to adhere to forensic standards and warns against tunnel vision. It is not merely a reconstruction of a pre-internet case. It is a question of how we ensure that justice does not fail again.

Read more

Ulvi Kulac
Profile

Ulvi Kulac

Peggy Knobloch
Case

Peggy Knobloch

Firebørn dræbt af fremmed mand i schweizisk horrornagt
Post

Swiss Home Invasion: The Rupperswil Murders and Europe's Largest Manhunt

Related Content
Ulvi Kulac

Ulvi Kulac

Peggy Knobloch

Peggy Knobloch

Firebørn dræbt af fremmed mand i schweizisk horrornagt

Swiss Home Invasion: The Rupperswil Murders and Europe's Largest Manhunt

Utah-mor dømt for mord på mand — udgav sorgebog til børn

Utah Mother Convicted of Poisoning Husband with Fentanyl

Advertisement
SS

Susanne Sperling

View all stories →
Share this post:
Böse Spiele: 20.000 Akten enthüllen Justizirrtum im Fall Peggy

20,000 Documents Expose Justice Scandal in Peggy Case

Investigative journalist Marc Thiel analyzes police files to prove innocent man wrongly convicted

Author
Susanne Sperling
Published
May 8, 2026 at 12:17 AM

Quick Facts

LocationBirkenfeld, Unterfranken, Bayern — Verschwinden von Peggy Knobloch
AuthorMarc Thiel, investigative journalist since 1997
Scope352 pages based on over 20,000 case file pages
PublisherRiva (Random House), 2024, ISBN 978-3-7423-1325-3
MethodAnalysis of court records under German procedure, no speculation

A Justice Scandal Documented Word for Word

Twelve-year-old Peggy Knobloch disappeared on July 7, 1996, from Birkenfeld, Germany. Nearly five years later, her remains were discovered in a forest, and shortly after, Ulvi Kulac was sentenced to 8.5 years in prison. But 2023 brought the truth to light: Kulac was innocent.

Journalist Marc Thiel spent decades investigating this case. In his new book "Böse Spiele"—based on 20,000 pages of police files—he systematically documents how an innocent man was convicted. The book was published in 2024 and presented on German television in a program comparable to the American "Unsolved Mysteries." German prosecutors confirmed to ZDF that Thiel's book is based on authentic documents and contributes to clarifying the case.

Why does this work matter internationally? Because it reveals wrongful convictions and investigative errors that can happen anywhere—including in your own country.

Systematic Failures in the Investigation

When Peggy was found, police wasted no time. In 2004, Ulvi Kulac was convicted based on so-called "overwhelming evidence." Even Germany's Federal Court of Justice upheld the sentence.

But Thiel's analysis reveals what actually happened:

- Fiber evidence was not conclusive but was interpreted too broadly

- DNA traces were misinterpreted in the laboratory

- Interviews used suggestive questions that "produced" a confession

- Alternative leads were never properly investigated

This form of tunnel vision in police work had catastrophic consequences for Kulac. After five years and eight months, he was released on probation in 2010, but only 13 years later—in 2023—was he officially declared innocent. German prosecutor Bamberg concluded that "modern tracing technology excludes any connection to Kulac."

This raises uncomfortable questions about unsolved murder mysteries and who is actually responsible for Peggy's death.

Modern Technology and New Hope

The case is far from closed. In 2023, the Bavarian criminal police reopened the investigation using modern DNA sequencing—a technique that did not exist in the 1990s. Police leadership declared: "The case is not archived. New technology gives us hope."

Peggy's mother, Lieselotte, has publicly expressed her hope for justice. Thiel's book helps keep the case in the public eye and ensures that all the mistakes are not forgotten.

An Important Lesson in Justice

For anyone interested in true crime cases or working in the legal field, "Böse Spiele" is essential reading. The book is not sensational speculation without foundation—it is a methodical examination of what went wrong.

Thiel has written a work that calls on police to adhere to forensic standards and warns against tunnel vision. It is not merely a reconstruction of a pre-internet case. It is a question of how we ensure that justice does not fail again.

Read more

Ulvi Kulac
Profile

Ulvi Kulac

Peggy Knobloch
Case

Peggy Knobloch

Firebørn dræbt af fremmed mand i schweizisk horrornagt
Post

Swiss Home Invasion: The Rupperswil Murders and Europe's Largest Manhunt

Related Content
Ulvi Kulac

Ulvi Kulac

Peggy Knobloch

Peggy Knobloch

Firebørn dræbt af fremmed mand i schweizisk horrornagt

Swiss Home Invasion: The Rupperswil Murders and Europe's Largest Manhunt

Utah-mor dømt for mord på mand — udgav sorgebog til børn

Utah Mother Convicted of Poisoning Husband with Fentanyl

Advertisement
SS

Susanne Sperling

View all stories →
Share this post: