The last of seven defendants in an ecstasy ring was sentenced to a dozen years in federal prison Thursday in Chattanooga.

Joel Head's sentencing followed a four-day trial in September for what federal prosecutors described in court documents as an ecstasy conspiracy designed by Head, Glenn Kamper and Jonathon St. Onge. Prosecutors alleged the trio sold the popular club drug in the Chattanooga area from October 2009 until they were arrested in January 2011.

But Head's attorney called the sentence a "travesty" and said prosecutors took the word of a "bald-faced liar" to build a case against his client and the other defendants.

Head, 37, was the only one of the seven to go to trial. A jury found him guilty of two counts in the six-count indictment -- conspiracy and ecstasy possession with intent to distribute.

St. Onge testified for the prosecution, claiming that Head, a lab technician at the Moccasin Bend Waste Water Treatment Plant, had the scientific knowledge and laboratory skills to make ecstasy.

Chief U.S. District Judge Curtis Collier said those skills were the main reason he sentenced Head to 12 years. Head could have been sentenced to anything between 11 and 14 years.

A group of teenage boys attending a summer program at McCallie School visited the courtroom during the sentencing hearing. Head asked to address them as they left before the hearing ended.

His wrists shackled to a waist chain, Head said to them, "If you guys ever run into bad influences in your life, stay away from them, otherwise this could happen to you."

Arrests in the case began with a 1-pound sale in on Jan. 19, 2011.

DEA Task Force Officer James Hixson wrote in court documents that he used a confidential source to buy a pound of ecstasy from Benjamin Park at 835 Clark St.

Surveillance teams spotted St. Onge and Christina Harris dropping off drugs for Park to sell.

St. Onge testified that he was the distributor and Kamper was the "ringleader" who financed the drug operation and headed sales.

He said Head cooked the product at a camper in Harrison and an undisclosed location in Georgia. He said the group sold an ounce or two of the drug a month for at least a year.

But Head's attorney, Aldous McCrory, said after the hearing that St. Onge is an admitted LSD, ecstasy and marijuana dealer who exploited his knowledge of criminal networks to get a better deal on prison time.

"St. Onge is a bald-faced liar who said and did anything he could to shorten his sentence," McCrory said.

"I don't think Mr. Head deserved 12 years and how we got to there, that's the system," McCrory said.

He plans to begin an appeal of Head's sentence today.