A former state trooper will likely avoid jail time after admitting in court Tuesday to possessing anabolic steroids.

Asked by a judge how he wanted to plead to the charge of possession of a controlled substance, Adam Longo replied, "Your honor, I'm guilty."

The 28-year-old will be sentenced in Natrona County District Court in the coming weeks for the felony. Under the plea agreement, the maximum penalty Longo could receive is five years of probation. He faced up to five years in prison before reaching a deal with prosecutors.

Longo's name surfaced during a Wyoming Division of Criminal Investigation probe of Franklin Ryle Jr., a former state trooper accused of kidnapping a Wal-Mart truck driver. During that investigation, authorities discovered anabolic steroids in Ryle's desk, according to a police affidavit.

In February, Longo walked into the office of Col. Sam Powell, the head of the Wyoming Highway Patrol, and admitted that he had used steroids during the previous 18 months and given some to Ryle.

According to police, Longo said he purchased the steroids at a Casper gym.

Speaking after Longo's arraignment Tuesday, District Attorney Michael Blonigen said several factors played into the plea agreement. Longo had no criminal record, and the anabolic steroids he admitted to having -- more than 0.3 grams of Cypiogen in liquid form -- was for personal use, Blonigen said.

"His cooperation has been extraordinary," the prosecutor noted.

Longo ceased working for the Highway Patrol in August. He was represented in court Tuesday by Casper attorney Michael Krampner.

The investigation into Longo's case revealed no connection with Ryle's federal kidnapping case, Blonigen said.

Ryle, who is in jail awaiting sentencing in the kidnapping case, is also accused of possessing steroids and conspiracy.

Another former state trooper, Devan Henderson, has also been arrested and charged with possession of anabolic steroids. Henderson, 34, told agents he and Ryle bought steroids while vacationing in Mexico in 2004 and brought them back to Wyoming in an empty vanilla bottle packed in a suitcase, according to a DCI agent's affidavit.

Henderson's arraignment is scheduled for Nov. 6.

Reach crime reporter William Browning at (307) 266-0534 or at william.browning@trib.com.