A special education teacher’s assistant at Mack Middle School was arrested Monday on a charge of lewdness with a child under 14, according to the Clark County School District.

Fausto Barraza-Balcazar (Las Vegas Metropolitan Police Department)

A special education teacher’s assistant at Mack Middle School was arrested Monday on a charge of lewdness with a child under 14, according to the Clark County School District.

An affidavit supporting an arrest warrant for Fausto Barraza-Balcazar, 59, said a teacher caught the man pressing his body against a 13-year-old student with autism in a laundry room at the school on May 10.

The teacher said the student was facing the washing machine with Barraza-Balcazar behind her, and there was no separation between them.

According to the affidavit, the student has the mental capacity of a 5-year-old. The teacher told police that Barraza-Balcazar and the student looked startled, and the student immediately ran to the bathroom.

The teacher reported the incident to the school principal, who reported it to school police that day. School police Lt. Darnell Couthen said a detailed investigation began the next day and continued until the beginning of June, when an arrest warrant was requested.

A sexual assault examination done at Sunrise Hospital and Medical Center came back negative, but the student told a forensic interviewer that the teacher’s assistant had touched her breast and vagina area.

The student said the touching made her mad and said “Mr. B.” had kissed and touched another student. Two other students who had contact with Barraza-Balcazar were scheduled for forensic examinations in May, according to the affidavit.

An interviewer was not able to get information from a 12-year-old autistic student, who would only say that “Mr. B. is bad,” according to the affidavit, which said the student has the mental capacity of a 2- or 3-year-old.

A third student, who is male and non-verbal, must wear a diaper. That student’s mother told police the child’s behavior had changed recently, and the teacher reported that Barraza-Balcazar was taking a long time to change the child’s diaper.

Joseph Chu, of Ladah Law Firm, said the 13-year-old victim’s mother reached out to his firm after the incidents that led to Barraza-Balcazar’s arrest. The mother asked about legal options for pursuing recourse on behalf of her daughter.

“This girl barely has a voice, in the most literal sense,” Chu said. “She wanted help in letting her daughter’s trauma be known.”

The girl and her family are “traumatized” and have undergone “intensive crisis counseling,” the lawyer added.

“The appropriate measures should have been taken to protect this girl, to ensure that these kind of life-changing traumas would never take place on the school’s watch,” Chu said. “… When it comes to special-needs students, like this particular victim, who are the most susceptible to unreported or concealed acts of abuse at the hands of unsupervised faculty or staff, clearly some measures need to be put into place to protect this particular class of students.”

According to the affidavit, police suggested a charge of unlawful contact with a child with a mental illness, in addition to the lewdness charge. Barraza-Balcazar is being held at the Clark County Detention Center without bail. He is due in court for a felony arraignment Wednesday morning.

Barraza-Balcazar has been employed with the school district since 2011, according to public records.

Las Vegas Review-Journal writers Lawren Linehan and David Ferrara contributed to this report. Contact Wesley Juhl at wjuhl@reviewjournl.com and 702-383-0391. Find @WesJuhl on Twitter.