SIOUX FALLS, S.D. (AP) — A South Dakota judge ruled Thursday that there’s no basis to keep sealed documents related to a child pornography investigation of billionaire banker and philanthropist T. Denny Sanford.

Judge James Power wrote that affidavits supporting search warrants should be made public under South Dakota law. But he said they would remain sealed until Sanford and his attorneys decide whether to appeal the ruling to the state Supreme Court.

Sanford attorney Stacy Hegge asked Power in an email last month to keep the affidavits sealed or at least be given additional time in order to seek relief from the Supreme Court. Hegge didn’t immediately reply to an email Thursday.

The South Dakota attorney general’s office declined to file charges against Sanford following the investigation, saying it found no “prosecutable offenses” within the state’s jurisdiction, according to a court document filed last month.

South Dakota investigators in 2019 began searching Sanford’s email account, as well as his cellular and internet service providers, for possible possession of child pornography after his accounts were flagged by a technology firm.

The investigation was first reported in 2020 by ProPublica and the Argus Leader. Both news outlets went to court for access to affidavits.

The 86-year-old Sanford is the state’s richest man, worth an estimated $3.4 billion.

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