Two officers acquitted after key evidence ruled illegally obtained in gambling probe leak case

Two police officers charged with leaking details of an illegal gambling investigation to a person connected to the case have been acquitted by the Supreme Court.

The Supreme Court upheld the appeals court's finding that the key evidence prosecutors submitted to prove the officers had passed on investigation details — a set of recorded phone calls — had been unlawfully obtained during a separate investigation.

The Supreme Court's First Division, presided over by Justice Cheon Dae-yeop, confirmed the acquittals of officers A and B, who had been indicted on charges of disclosing official secrets, on June 25.

The case began in July 2019, when police raided an illegal gambling operation set up in an apartment in Gyeonggi Province. According to court records, C, who had been running errands for the gambling den, contacted officer A — a police officer at the local precinct whom C knew personally — to ask about the status of the investigation.

C asked A whether it would be possible to handle the case by taking responsibility himself in place of D, who was suspected of actually running the gambling den, and whether there was any way to be charged with aiding and abetting the operation rather than running it. A said he would look into the matter and went to officer B, who was handling the case. B was found to have shown A the investigation records.

A then told C that he had seen photographs of the case file, disclosed the existence of evidence contained in the investigation records, and informed C that C had not yet been booked as a suspect. A and B were indicted in 2022 on charges of disclosing official secrets.

In 2023, the first-instance court found both officers guilty and sentenced A to six months in prison, suspended for one year, and B to two months in prison, suspended for one year. The court found that the officers, despite being bound by a duty to keep official secrets, had disclosed to C the existence of key evidence in the investigation records and whether C had been booked as a suspect.

The appeals court last year overturned those convictions, however, noting that the officers' alleged leak had come to light not during the illegal gambling investigation itself but in the course of a separate probe, and acquitted both officers.

According to court records, prosecutors in 2022 were investigating C on charges of issuing false tax invoices for profit in violation of the Act on the Aggravated Punishment of Specific Crimes. During that investigation, C voluntarily submitted a mobile phone, which prosecutors subjected to forensic analysis. In the process, investigators found three recorded phone calls from 2019 between C and officer A relating to the illegal gambling case, and used those recordings as the basis for indicting the officers on the secret-disclosure charges.

The appeals court ruled the recordings inadmissible. It found that phone calls unrelated to the false tax invoice case could not be subject to seizure, and that prosecutors had conducted an unlawful search and seizure by re-examining a cloned copy of the phone after the seizure procedures for the separate case had concluded. With the key evidence excluded, the appeals court found insufficient grounds to sustain the secret-disclosure charges and overturned the first-instance verdict, acquitting both officers.

The Supreme Court reached the same conclusion. The court said that "evidence obtained by investigative authorities through a warrantless search and seizure of electronic information beyond the scope of what is subject to seizure from a voluntarily submitted data storage device constitutes illegally obtained evidence," and that "the illegality is not cured even if a warrant is subsequently issued by a court."

The court further ruled that "an investigative authority's review of a cloned copy retaining unrelated information for the purpose of investigating new criminal suspicions is no different from conducting a warrantless search of electronic information not seized under a search and seizure warrant."