A beverage wholesaler from the Rhineland had been struggling with significant inventory discrepancies for over a year. Since the company did not operate any retail or warehouse sales but exclusively handled deliveries, and there were no signs of break-ins at the company premises, it was reasonable to conclude that one of the employees must be responsible for the missing inventory. Various indications pointed to a specific delivery driver, Mr. Wiehl. The detectives of the Aaden Corporate Detective Agency Cologne were tasked with surveilling this target person during his delivery routes and determining whether he adhered to the route plan, actually delivered the specified quantities ordered by customers, and did not misappropriate any goods.
After consultation with the client, review of the route plans for the coming week, and assessment of the local conditions, our observers positioned themselves on a Monday morning to monitor the target person Wiehl. Until early afternoon, the delivery driver appeared to fulfill his duties properly and worked through his customer list. The exact number of unloaded beverages could usually not be verified by our Cologne detectives, as the delivery vehicle was always positioned very close to the customers’ buildings with the tailgate lowered.
When the target person completed his final stop and was on the road back to the client company, our corporate detectives from Cologne already expected the operation to conclude shortly. However, the delivery vehicle unexpectedly turned into a narrow dead-end street with private homes and garages. To avoid drawing attention in the confined space, the observers parked their vehicles at a distance and approached on foot to maintain visual contact with the target vehicle, which was parked at a garage. The garage door was open, and the rear of the transporter was accessible. Using a hand truck, Mr. Wiehl and an unknown male moved beverage crates from the delivery vehicle into the garage. After approximately 30 minutes, the two men finished their activity and parted ways. The unknown individual entered a neighboring residence, while Mr. Wiehl returned to the beverage wholesaler and parked his company vehicle there. After consulting with the client, one of the Aaden detectives Cologne ended surveillance for that day, while his colleague continued observing the garage to determine whether the stored goods would be sold or transported further.
On the second day of surveillance, our private detectives from Cologne already observed deviations from the route during the delivery: three addresses were visited and apparently supplied that were not on the list. Additionally, at the end of his shift, Mr. Wiehl appeared to take a half-hour break at his private residence before returning to his employer and clocking out. This raised further suspicion of time theft.
One of our Cologne corporate detectives went to the garage after the target person returned to the company. However, no further activity was observed that day, so surveillance of the garage was scheduled for Wednesday, when Mr. Wiehl had a day off. In the morning, the unknown male appeared, opened the garage, and began performing manual work. Under an appropriate pretext, our detective from Cologne approached and looked inside the garage: all beverages were gone. Therefore, since Monday, the goods must have been resold, transported, or—given the quantity, highly unlikely—consumed.
On the following Thursday, two investigators from the Aaden Detective Agency Cologne again surveilled the target person during his delivery route. Once again, stops were made that were not part of the official route plan. As the deliveries came to an end, the detective team split up as before: one observer continued following Mr. Wiehl, while the other kept the garage under observation. The two investigators soon reunited, as only a few minutes after the unknown male appeared at the garage, Mr. Wiehl’s delivery vehicle also entered the dead-end street. As on Monday, the two perpetrators unloaded approximately 70 beverage crates as well as various cartons of wine and spirits into the garage. Afterward, both left the scene, while the Aaden detectives Cologne remained to determine what would happen to the stolen goods.

Mr. Wiehl and his unknown accomplice moved large quantities of beverage crates belonging to the clients of our Cologne detectives into a garage.
From early afternoon onward, various vehicles began arriving at the garage. Each time, the unknown male appeared, unlocked the garage, and loaded beverages into the trunks in exchange for cash payments. One observer followed the buyers each time – all appeared to live within a few kilometers. The quantities purchased ranged between five and twelve crates or cartons.
On Friday, the existing evidence was further substantiated by additional observations, during which Mr. Wiehl and his accomplice once again unloaded beverages belonging to the client company into the garage. After the delivery route ended, our corporate detectives from Cologne revealed their findings:
After work, Mr. Wiehl was asked by his superiors to come to an office at the company location. There, three Aaden detectives Cologne were already waiting, asked him to sit down, and presented the investigation reports and photographic evidence from the past days. After an initial shocked silence and after our investigators informed him that his only chance of avoiding criminal prosecution was to cooperate with our private detectives, Mr. Wiehl confessed: for over two years, he had regularly stolen beverages, initially in small quantities, but as these went unnoticed, he escalated the scale. Within a few months, he had partnered with his accomplice, whose identity he disclosed, and together they sold the stolen goods commercially to informed friends and acquaintances.
He estimated the total value of the stolen goods at €220,000.
In coordination with the affected company, the Aaden Corporate Detective Agency Cologne proposed to Mr. Wiehl that criminal charges would be waived if he signed an immediate termination agreement for his employment and a notarized acknowledgment of debt with a repayment agreement. Without hesitation, he agreed and immediately accompanied the detectives to a previously informed notary to certify the documents.
Following the signed confession, Mr. Wiehl summoned his accomplice to the garage under a pretext. Upon arrival, the individual opened the garage to receive further (previously promised) deliveries from the target person. The accomplice was visibly surprised when our Cologne investigators appeared and identified themselves as detectives. It took less than two minutes for him to agree to sign the acknowledgment of debt, provide the names and addresses of three primary buyers, and accompany two witnesses to the notary. Before that, the remaining stolen goods in the garage were secured, although these were only the remnants of the beverages unloaded earlier that day—an indication of the scale at which stolen goods had apparently been sold on a daily basis. Further claims against the buyers were initiated through legal counsel.
Note: For reasons of discretion and data protection, the locations of operations and certain personal details have been modified without materially altering the actual events.
Aaden Detectives Cologne
Hohenstaufenring 62
D-50674 Köln | Cologne
Tel.: +49 221 9859 2399
E-Mail: info@aaden-detektive.de
Web: https://aaden-detektive.de/en
CEO: Maya Grünschloß, PhD
Register Court: Amtsgericht Köln
Registration Number: HRB 83824
Tags: Detective Agency, Cologne, Detective, Corporate Investigator, Employee Monitoring, Surveillance, Detective Office, Private Detective, Corporate Detective Agency, Detective Services, Theft, Acknowledgment of Debt, Fence, Misappropriation, Detective Team, Notary, Commercial, Handling Stolen Goods