Robert Pimentel, 57, former teacher at George de la Torre Elementary School in Wilmington, during an arraignment for sex abuse charges at  L.A. County
Robert Pimentel, 57, former teacher at George de la Torre Elementary School in Wilmington, during an arraignment for sex abuse charges at L.A. County Superior court in Long Beach, Calif., on January 24, 2013. (Jeff Gritchen / Staff Photographer)

Related: Former Wilmington elementary school teacher arrested on molestation charges

The principal of the school where a fourth-grade teacher was arrested on suspicion of molesting 20 students took no action when similar allegations were leveled a decade earlier against the teacher at another school, LAUSD Superintendent John Deasy said Thursday.

Robert Pimentel, 57, of Newport Beach was arrested Wednesday on charges of abuse that allegedly took place last year at George De La Torre Jr. Elementary in Wilmington. He was arraigned Thursday in Long Beach and is being held on $12 million bail.

When sex-abuse complaints against Pimentel surfaced in March 2012, Deasy said, he learned that the veteran educator had previously been accused of misconduct in 2002, while he was teaching at Dominguez Elementary in Carson.

Pimentel was transferred to De La Torre in 2007, records show. Deasy said parents there complained the following year that he was improperly touching students.

Irene Hinojosa had been Pimentel's principal at both Dominguez and De La Torre Elementary schools, according to district records.

Deasy said he removed Hinojosa from her position last March - about the same time that Pimentel was pulled from the classroom - after a review of personnel files showed she hadn't acted on the previous allegations.

"That's why I moved to fire both the teacher and the principal - the teacher for misconduct and the principal for failing to notify authorities," Deasy said. "There was sufficient grounds, their behavior warranted separation.

LAUSD elementary school teacher Robert Pimentel, 57, left, with his attorney, Richard Knickerbocker, center, during an arraignment for sex abuse charges
LAUSD elementary school teacher Robert Pimentel, 57, left, with his attorney, Richard Knickerbocker, center, during an arraignment for sex abuse charges with Judge James Otto, right, at L.A. County Superior Court in Long Beach, Calif., on January 24, 2013. Pimentel, who taught at George de la Torre Jr. Elementary School in Wilmington, Calif., is facing 15 charges against Pimentel involving a dozen alleged victims. (Jeff Gritchen / Staff Photographer)
"

Deasy planned to ask the school board in April 2012 to fire both Pimentel and Hinojosa, but they both retired before the scheduled meeting. That means that both will be receiving their pension benefits.

"They both retired on the same day," Deasy said. "It's clear they did it to prevent me from going to the school board."

Hinojosa could not be reached for comment.

Parents of children at the Wilmington school were informed within 72 hours after Pimentel was removed from the campus, and the state Commission on Teacher Credentialing was promptly notified, the district said.

However, the CTC website shows that the licenses of Pimentel and Hinojosa are still valid.

A CTC representative said the commission will take up the question of Hinojosa's credentials during a closed session meeting scheduled for Jan. 31. As for Pimentel, the official said the commission automatically suspends all credentials as soon as it receives documents from an arresting agency showing charges involving sex offenses.

Pimentel's arrest on Wednesday capped a 10-month investigation into allegations that he'd improperly touched students during the school day.

In court Thursday before Superior Court Judge James D. Otto, Pimentel pleaded not guilty to eight counts of continuous sexual abuse and seven counts of lewd acts upon a child.

Police and school officials say Pimentel also is suspected of the sexual abuse of one adult, but they did not say what role, if any, that person had at the school.

Pimentel's attorney, Richard Knickerbocker, called his client "an exemplary citizen," saying he is not guilty of all charges.

"He has no arrest record," Knickerbocker said. "He was an outstanding teacher and a soccer coach."

Knickerbocker also said the charges are the result of a single complaint two years ago against Pimentel "that were blown out of proportion. It was not an inappropriate touch."

The school then searched for other parents and coached them into saying Pimentel also touched their children, Knickerbocker claimed. 

Calling his client's $12 million bail "abusive," Knickerbocker said he will appeal the amount.

Pimentel is scheduled to return to court on Jan. 31 in Long Beach.

barbara.jones@dailynews.com

Follow Barbara Jones on Twitter at http://twitter.com/LADNschools

Staff writer Brian Sumers contributed to this article.