PROVO — Prosecutors filed 21 felony charges Friday against a former LDS seminary principal who they allege developed a sexual relationship with a 16-year-old student.

Michael J. Pratt, 37, was charged in 4th District Court with 10 counts of forcible sodomy, seven counts of object rape and two counts of rape — all first-degree felonies, said prosecutor Ryan Peters.

Pratt was also charged with two second-degree felonies of forcible sex abuse, according to charging documents filed in 4th District Court.

"We do believe we have the probable cause for those charges," Peters said.

Peters couldn't comment on the value of their evidence but said their office and police officers have done an "extensive investigation."

Police arrested Pratt July 9, after they received information that he had allegedly been checking the girl out of school without her parents' permission and taking her to various locations for sexual encounters.

Pratt took the girl to a boxcar near Vivian Park in Provo Canyon, up Rock Canyon, to a mine in Eureka and the warm springs near Goshen, where they were also observed skinny-dipping, according to a police affidavit.

The charging document indicates the sexual abuse began May 8 and continued until June 25. The investigation also revealed hundreds of text messages sent between the two, including some that were sexually explicit, according to the affidavit.

Pratt had been employed at Lone Peak High School's seminary program, according to Kim Farah, spokeswoman for The Church of Jesus Christ of Latter-day Saints. He was terminated when the allegations surfaced.

Pratt will appear in court Monday at 8:30 a.m., where he will be formally presented with the charges. At that time, he can request a public defender. He is out of custody after bailing out of jail on $20,000 cash-only bail.

At a hearing Monday intended to review his bail, Pratt became emotional as he addressed the media.

"I am hopeful that the truth will be fully presented at the appropriate time," he said.

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