June 15, 2023 Sylvan Larrabee, 31, of Pierre, convicted of failure to register as a sex offender, was sentenced on June 12, 2023 to 17 months in federal prison, followed by five years of supervised release, and ordered to pay a $100.00 special assessment to the Federal Crime Victims Fund. Larrabee was indicted by a federal grand jury in February of 2023 and pled guilty on March 16, 2023. The convi…