A witness's testimony will prove that a former undercover agent who sent dozens of blacks to prison on bogus drug charges perjured himself, a prosecutor said in opening statements Tuesday.

Former police officer Tom Coleman (search) is accused of lying about his arrest record in evidentiary hearings for four defendants in 2003. If convicted of two felony charges of aggravated perjury, he could be sentenced to 20 years in prison and a $20,000 fine. Prosecutors dropped a third charge Monday but did not say why.

"At the end of the case there will be no doubt he lied," prosecutor Rod Hobson said.

One of the perjury counts stems from Coleman's statements regarding 1998 charges that he stole gas while working as a county sheriff's deputy.

Hobson told jurors they will hear from someone who says they saw Coleman pumping gas intended for official use into his personal pickup.

According to testimony, Coleman used a gas card to fill up twice on May 18, 1998, the second time after having traveled just 36 miles.

He also used a card after he quit his job in the middle of a shift, telling a dispatcher, "I really don't want to resign but I got to," according to testimony from dispatcher Helen Drennan.

Drennan testified that Coleman told her he had just gotten a letter from his wife that said she was leaving him.

Defense attorney John H. Read II did not make an opening statement Tuesday, reserving the right to do so later.

Coleman built cases and made arrests for 18 months in the late 1990s as part of the Panhandle Regional Narcotics Trafficking Task Force (search). He used no audio or video surveillance to substantiate drug buys, and no drugs or money were found during the arrests.

Of 46 people he arrested, 38 — most of them black — were convicted of selling small amounts of cocaine and received sentences of up to 90 years.

The cases drew international attention after civil rights groups, including the National Association for the Advancement of Colored People (search), questioned whether the drug sting was racially motivated.

Last year, 45 of those arrested split a $6 million settlement of a civil rights lawsuit against Coleman and the 26 counties and three cities involved with the task force.

A jury of 11 white people and one Hispanic is hearing the trial, which is expected to last about a week. The judge has issued a gag order.