The 13-year-old wisp of a girl on the witness stand raised her arm and pointed to the defendant seated in the courtroom and flatly answered the question from the prosecutor.

"I'm here today because (he) raped me," she said Monday.

She was the first witness in the trial of Shaun Hamilton, who is accused of sexually assaulting her and another young woman nearly seven years ago.

She spoke after the prosecutor and Hamilton's defense attorney made their opening statements to a mostly male jury in the courtroom of Natrona County District Court Judge Daniel Forgey.

Hamilton is charged with one count of first degree sexual assault, two counts of first degree sexual abuse of a minor, and two counts of second degree sexual abuse of a minor. If convicted on all counts, he could spend decades in prison.

Assistant District Attorney Kevin Taheri told the jury that Hamilton assaulted the girl, who now lives out of state, a year ago.

The next day, a friend at school asked her what was wrong. The answer lead to a talk with the principal and then a worker with the Wyoming Department of Family Services, an interview at the Children's Advocacy Project, and the administration of a rape kit at the Wyoming Medical Center.

The kit, a blanket, and evidence taken from Hamilton himself were sent to the Wyoming Crime Lab, which determined Hamilton's DNA was on the girl, Taheri said.

The investigation of this case lead to the re-opening of another alleged incident involving Hamilton in 2009, he said.

But defense attorney Hampton Young told the jurors they should be wary of the case from 2009, and ask why it is only being addressed now.

Victims have given conflicting statements, and DNA evidence does not necessarily prove the allegations of sexual assault unlike the simply solved crimes seen on CSI television shows, Young said.

Jurors also should ask themselves why a case from 2009 and investigated in 2010, is being revived now, he said.

The trial resumes Tuesday morning.