By Blake Brittain

Feb 24 (Reuters) - Google GOOGL.O did not violate a Google Photos user's rights when it reported child sexual abuse material in his library that was used to criminally charge him, the Wisconsin Supreme Court determined on Tuesday.

The court said in a unanimous decision that Google's actions did not implicate Andreas Rauch Sharak's rights under the U.S. Constitution's Fourth Amendment by flagging his content.

Rauch Sharak's attorney and a spokesperson for Google did not immediately respond to requests for comment on the decision.

Google, which scans user content for potential child sexual abuse material, flagged four of Rauch Sharak's files to the National Center for Missing & Exploited Children in 2021. The group forwarded Google's tip to the Wisconsin Department of Justice, and a sheriff discovered the images on Rauch Sharak's phone after executing a search warrant based on the tip.

The state charged him with 15 counts of possession of child sexual abuse material. Rauch Sharak argued Google violated his Fourth Amendment rights by searching his files as a government actor without a warrant.

A Wisconsin lower court rejected Rauch Sharak's argument and the state's Supreme Court upheld that decision on Tuesday, finding Google was not subject to the Fourth Amendment's prohibitions against unreasonable government searches and seizures.

"The government became involved only after Google scanned, opened, and viewed Rauch Sharak’s files," the court said. "That lack of government involvement suggests Google was not acting as an instrument or agent of the government."

The case is State of Wisconsin v. Rauch Sharak, Supreme Court of Wisconsin, No. 2024AP469-CR.

For Rauch Sharak: Brad Novreske of Novreske Law Office

For Wisconsin: Michael Conway of the Wisconsin Department of Justice

(Reporting by Blake Brittain in Washington)