A Seneca Valley graduate on Monday testified that his high school career was marred by frequent sexual assaults by one of his Junior ROTC instructors.

“This man ruined and stole three and a half years of my life,” the alleged victim told a Butler County jury in the opening day of trial for Sgt. Maj. Kevin Johnson, 54.

Now 22, the man is one of two alleged victims expected to testify that they were molested by Johnson while involved in the school program before 2008.

Johnson, who claims he is innocent, faces numerous charges. His trial before Butler County Judge Timothy McCune is expected to continue today and conclude before the weekend.

“This is a case of abuse and betrayal,” Assistant District Attorney Mark Lope told the jury in his opening statements.

Lope called the alleged victims “brave young men.” And he promised the jury that the prosecutors would present testimony and evidence, including DNA, to corroborate their accusations.

On Monday only one of the two alleged victims testified.

Wearing a tie and suit, the man spoke softly but in a frank manner. He told the jury that he became interested in the Junior ROTC program when he was in the eighth grade because his family has ties to the military and the program “looked promising.”

The alleged victim claims that as a 15-year-old freshman, Johnson —- one of the program's two instructors at that time — began sexually assaulting him.

And as his high school career progressed so did the assaults, escalating both in frequency and in the types of sexual acts, the alleged victim testified.

The pair eventually engaged in sexual acts multiple times a week in the JROTC area of the school as well as another location on the campus, in Johnson's car, and on a field trip.

“Any chance we could get, we'd do these acts,” the man said.

The man told the jury he was never forced to have sexual relations with Johnson. On the contrary, the man testified, “He (Johnson) told me he loved me and that made me feel special.”

The alleged victim told the jury that Johnson played video games and talked online with him. And the alleged victim claimed that Johnson bought him hamburgers or pizza and clothes or shoes.

Meantime, the alleged victim testified he told his parents that Johnson, who sometimes picked him up early for school, was helping him with physical and academic improvement.

“My parents always thought it was great I had this type of mentor in my life... someone who was helping me succeed,” the man testified.

The alleged victim told the jury the assaults stopped only after the other alleged victim in this case contacted Jackson Township police in January 2008.

But in response to the testimony, Johnson's defense attorney, David Shrager, pointed out to the jury what he claims are inconsistencies in the accuser's story, such as when the assaults started. He reportedly told investigators previously that the assaults began when he was 16.

In one question, Shrager stopped just short of calling the alleged victim a liar by pointing out what he had testified to earlier, and asking what that type of response is called.

“What's that three letter word?” Shrager asked.

The alleged victim denied Shrager's accusation that he had threatened to claim that he was molested by Johnson before the accusations surfaced. And, Shrager pointed out, the alleged victim already filed a lawsuit in this case.

The alleged victim told the jury that his lawsuit was settled for $100,000 “from the school.” After paying lawyers and splitting the settlement with the other alleged victim, this man said his share was $30,000.

Eight of Johnson's family members, including his wife and mother, sat behind him in court Monday.

This is the second time this case has gone to a jury trial.

A trial that began Aug. 17, 2009, ended just minutes into testimony from the first witness, Jackson Township Police Chief Len Keller.

McCune declared a mistrial after Keller testified that Johnson had declined to take a polygraph test.

During a subsequent hearing, Keller testified that he knew polygraph results are inadmissible, but he believed he could tell the jury he asked Johnson to take the test.

Shrager later argued to McCune that prosecutors should be barred from holding another trial based on double jeopardy. McCune refused the request, and the state's Superior Court upheld that decision in July 2010.

Although Keller sat at the prosecution's table, he did not testify on Monday.