Best Buy Geek Squad agent Josh Sorensen replaces a motherboard on a laptop at Geek Squad City in Brooks, Ky., in a 2012 file photo. A child pornography case launched at the facility led to the discovery that eight Geek Squad technicians had served as paid informants for the FBI. (Ken James/BLOOMBERG NEWS)

At a giant Best Buy repair shop in Brooks, Ky., Geek Squad technicians work on computers owned by people across the country, delving into them to retrieve lost data. Over several years, a handful of those workers have notified the FBI when they see signs of child pornography, earning payments from the agency.

The existence of the small cadre of informants within one of the country’s most popular computer repair services was revealed in the case of a California doctor who is facing federal charges after his hard drive was flagged by a technician. The doctor’s lawyers found that the FBI had cultivated eight “confidential human sources” in the Geek Squad over a four-year period, according to a judge’s order in the case, with all of them receiving some payment.

The case raises issues about privacy and the government use of informants. If a customer turns over their computer for repair, do they forfeit their expectation of privacy, and their Fourth Amendment protection from unreasonable searches? And if an informant is paid, does it compromise their credibility or effectively convert them into an agent of the government?

Best Buy searching a computer is legal — the customer authorized it, and the law does not prohibit private searches. But if Best Buy serves as an arm of the government, then a warrant or specific consent is needed. And a federal judge in the child pornography case against Mark Rettenmaier is going to allow defense attorneys to probe the relationship between Best Buy and the FBI at a hearing in Los Angeles starting Wednesday.

“Their relationship is so cozy,” said defense attorney James D. Riddet, “and so extensive that it turns searches by Best Buy into government searches. If they’re going to set up that network between Best Buy supervisors and FBI agents, you run the risk that Best Buy is a branch of the FBI.”

The FBI and Justice Department declined to comment. Federal prosecutors argued in California that when a technician doing repairs “stumbles across images of child pornography” and the government wasn’t aware of the search, “the technician is clearly not performing the search with the intent of assisting law enforcement efforts.”

Best Buy spokesman Jeff Shelman said in a statement Monday that “Best Buy and Geek Squad have no relationship with the FBI. From time to time, our repair agents discover material that may be child pornography and we have a legal and moral obligation to turn that material over to law enforcement. We are proud of our policy and share it with our customers before we begin any repair.”

Shelman added, “Any circumstances in which an employee received payment from the FBI is the result of extremely poor individual judgment, is not something we tolerate and is certainly not a part of our normal business behavior.” Court records did not detail how often or how much the technicians were paid, other than one $500 payment to one supervisor.

But emails between Geek Squad technicians and FBI agents in the Louisville field office indicate a long-running relationship. In revealing those publicly in a Dec. 19 order, U.S. District Judge Cormac J. Carney required technicians and agents to take the witness stand this week. The ruling was first reported by Orange County Weekly.

Many of the documents establishing the ties between the FBI and the technicians are sealed, but Carney discussed some in his order. He noted that the FBI acknowledged it considered technician supervisor Justin Meade a confidential human source for all but a few months between October 2008 and November 2012.

Different agents handled the Geek Squad technicians, Carney wrote. In October 2009, Agent Jennifer Cardwell emailed Meade to express interest in meeting “to discuss some other ideas for collaboration,” Carney disclosed.

In an internal FBI communication in July 2010, Agent Tracey L. Riley told her supervisor that “Source reported all has been quiet for about the last 5-6 months, however source agreed that once school started again, they may see an influx of CP [child pornography].” Meade was later identified as the “source.” Other internal communications show the “source” referring possible cases to Riley from computers sent to the Geek Squad from across the country.

“This two-way thoroughfare of information,” Riddet, the defense attorney. argued in his motion to suppress the evidence, “suggests that the FBI considers [Meade] . . . to be a partner in the ongoing effort of law enforcement to detect and prosecute child pornography violators. . . . Here it is very clear that Best Buy, and specifically the supervisor who reports its technician’s discovery of ‘inappropriate’ content on customers’ computers, are not only working together, but actually planning to conduct more such searches in the future.”

The case started in November 2011, when Rettenmaier, a gynecological oncologist in Orange County, Calif., took his HP Pavilion desktop to the Best Buy in Mission Viejo, Calif., because it wouldn’t boot up. The technicians at the store told him he had a faulty hard drive. If he wanted to retain information from the hard drive, he would need the Geek Squad’s data recovery services in Kentucky.

Rettenmaier signed a service order that prosecutors argue “waived any right to raise a Fourth Amendment claim” because it contained the admonition: “I am on notice that any product containing child pornography will be turned over to the authorities.”

Rettenmaier’s hard drive was shipped to Geek Squad City in Brooks, Ky., a suburb of Louisville. In December 2011, one of Meade’s technicians located a photo that Riddet described as a nude prepubescent girl on a bed. In January 2012, court records show Meade emailed Agent Riley in Louisville and said, “We have another one out of California we want you to take a look at, when can you swing by?”

Meade did not respond to phone and email messages. Prosecutors acknowledged that the FBI paid him $500 in October 2011, two months before his co-worker discovered the photo. Meade filed a sworn declaration last year that “I do not remember ever being paid by the FBI.”

The search of Rettenmaier’s hard drive has a further wrinkle. The image was located on “unallocated space,” which is where deleted items reside on a computer until they are overwritten when the space is needed. Unallocated space is not easily accessed — it requires special forensic software.

Prosecutors said that the Geek Squad technician who searched the unallocated space was merely trying to recover all the data Rettenmaier had asked to be restored. Riddet argued that the technician was going beyond the regular search to deleted material to find evidence the FBI might want.

In addition, a federal appeals court has ruled that pornography found on unallocated space is insufficient to prove that the user possessed it, since information about when it was accessed, altered or deleted is no longer available. “There was no evidence of how the contraband got onto Dr. Rettenmaier’s hard drive,” Riddet wrote, “and it could have gotten there before he possessed the computer or against his will.”

An internal FBI email indicated that agents knew charges were unlikely based on an image in unallocated space. But prosecutors did authorize a search warrant for Rettenmaier’s computer and home, which was executed in February 2012. It is unclear why Rettenmaier was not indicted until almost three years later, in November 2014.

Judge Carney will allow Rettenmaier’s lawyer to question not only the Best Buy technicians and FBI agents involved in the case, but also the federal prosecutor who authorized the searches at the upcoming hearing. “The relationship between the FBI and Best Buy [informants] prior to Rettenmaier’s hard drive’s repair,” Carney wrote, “is relevant to how Meade understood his role as an informant and the possibility of an agency relationship between those who specified [the technician’s] procedures and the government.”

Best Buy’s Shelman said, “To be clear, our agents unintentionally find child pornography as they try to make the repairs the customer is paying for. They are not looking for it.” He said store policy bars agents from doing “anything other than what is necessary to solve the customer’s problem.”

Stan Goldman, a law professor at Loyola Law School, likened Best Buy’s search to the “plain view” doctrine for police: If officers can see something in plain view, they have reason to search or seize it. “Whatever they see while searching within the scope of what they were asked to do would be admissible, in my view,” Goldman said. “If they start searching on their own, they’ve gone beyond what is ‘plain view.’ ” He said what a customer consents to when ordering the work is crucial. “Have people actually understood that they’ve agreed to have their entire computer searched? I don’t think so, but you can’t be 100 percent certain.”

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