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Attorney General Marty Jackley

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Sioux Falls Man Pleads Guilty to Child Pornography Charges

Sioux Falls Man Pleads Guilty to Child Pornography Charges

(Pierre) – Matthew Lee Mierkey, Sioux Falls, pled guilty to 30 counts of possession of child pornography today. Mierkey could face up to two years in prison and a $2,000 fine per count. A pre-sentence investigation has been ordered, no sentencing date has been set. Mierkey remains in custody.

“This guy had a ton of child pornography on his computer. He’s a registered sex offender. Every time we arrest one of these guys we make South Dakota a little safer for the kids,” said Deputy Attorney General Larry Long.

The South Dakota Division of Criminal Investigation, in conjunction with the Sioux Falls Police Department arrested Mierkey in April.  His arrest was the first stemming from Operation Avalanche. 

Operation Avalanche was a Texas Law Enforcement investigation of a child pornography website.  Texas Law Enforcement forwarded the names of website subscribers to the home states of those subscribers. The South Dakota Division of Criminal Investigation and the Governor’s Internet Crimes Against Children Unit work together on the execution of search warrants and the analysis of computers seized through Operation Avalanche.

The leads from Operation Avalanche have led to the execution of 20 search warrants and 6 arrests in South Dakota.

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