A federal judge has sentenced a Madison, South Dakota, man to 10 years in prison for attempting to entice a person he believed was a 13-year-old girl, closing a case that began with an undercover investigation in Iowa.
Chief U.S. District Judge Roberto A. Lange sentenced Lawrence Johnson, 51, on August 31. The U.S. Attorney’s Office for the District of South Dakota announced the outcome on September 8. Johnson was also ordered to serve five years of supervised release, register as a sex offender and pay a $100 assessment.
Undercover investigation
According to federal prosecutors, an investigator with the Des Moines County Sheriff’s Office communicated with Johnson from September 15 through October 10, 2024, while posing online as a 13-year-old named “Abby.” Johnson sought nude images and tried to persuade the purported child to travel to South Dakota for sex.
After his arrest, Johnson admitted the conduct and acknowledged that he believed he was communicating with a real child, prosecutors said. No actual child was involved in the undercover exchange.
Conviction and sentence
A federal grand jury indicted Johnson in December 2024. He pleaded guilty on June 1, 2026, to attempted enticement of a minor using the internet. His conviction is established by that plea; it is no longer merely an accusation. The court remanded him to the custody of the U.S. Marshals Service after sentencing.
The Des Moines County Sheriff’s Office, South Dakota Division of Criminal Investigation and Homeland Security Investigations conducted the investigation. Assistant U.S. Attorney Elizabeth Ebert-Webb prosecuted the case.
Why the case matters
Undercover operations can interrupt attempted exploitation before an offender reaches a child, but they also require prosecutors to prove criminal intent despite the absence of an actual minor. Johnson’s admissions and guilty plea resolved that issue in this case.
The Justice Department’s announcement does not describe arguments from Johnson’s defense at sentencing or explain how the judge selected the statutory term. The public notice also does not say whether he intends to appeal.
Source: U.S. Attorney’s Office for the District of South Dakota, September 8, 2026.
