Private investigations of Constantia Oomen

Constantia Oomen is a California-based author and investigator originally from the Netherlands whose work focuses on pseudoscience, fraud, skepticism, and unresolved mysteries. Her investigations began with the Dutch “paranormal medium” Robbert van den Broeke and his associates, a network that ultimately intersected with the Joran van der Sloot and Natalee Holloway case.

Over the years, Parameter expanded into investigations of the Dutch Skeptic Society, the Neofolk band Darkwood, claims of mediumship and paranormal phenomena, and broader explorations of skepticism, magical realism, and anomalous experiences.

In 2023, Constantia turned her attention to another controversial American mediumship case. More recently, her work has focused on a renewed investigation into the disappearance of Natalee Holloway, including research into St. Anna Cemetery on Aruba.

Her latest investigation, Inside La Familia: eBay Live, takes a close look at OG Jewelers, the psychology and social dynamics of its eBay Live community, unusual sales formats, and how some of those practices relate to eBay’s own published policies.

Constantia is also the author of the true-crime books Genverbranders and Gene Burners: Paranormal Fraud, Casino Fraud, and Murder – Behind the Scenes of Robbert, Stan and Joran, as well as the memoir Another Davis, published in Dutch, English, and German.

Parameter serves as the central archive of her investigations, articles, research notes, books, and ongoing projects.

🇳🇱 Inhoud kan als schokkend ervaren worden
🇺🇸🇬🇧 Content can be experienced as disturbing
🇩🇪 Achtung, der Inhalt kann als schockierend empfunden werden
🇪🇸 El contenido puede experimentarse como impactante
🇫🇷 Le contenu peut être ressenti comme choquant
🇸🇪 Innehållet kan upplevas som chockerande
🇦🇼 E contenido por wordo eksperensiá como algo perturbador.
🇳🇱* Inhoud kin es sjokkerend ervaore waere.

🔨 New – September 10, 2026

🇺🇸🇬🇧 Inside La Familia: eBay Live
🇩🇪 La Familia: eBay Live von innen
🇳🇱 Binnen bij La Familia: eBay Live

🔍 Currently Investigating

Natalee Holloway Investigation
There have been new developments in this investigation, but I am withholding the details for the time being.
Last updated: June 21, 2026