Lawsuit alleges sexual abuse of girls at Los Lunas residential treatment center

A civil complaint filed March 5, 2026 in New Mexico’s First Judicial District Court alleges that the Sandhill Center, a residential treatment facility near Los Lunas, allowed staff to sexually abuse girls ages 8 to 14 over an extended period. The suit was filed on behalf of a former resident who says she was admitted to Sandhill at age 11 and was sexually assaulted by staff member Sergio Martinez beginning around Christmas 2008 and continuing into spring 2009, the complaint states.

The complaint details where and how the plaintiff says the assaults occurred: many of the alleged assaults on the plaintiff took place in a neurofeedback room at the facility, and Martinez is accused of taking at least three girls to his home despite rumors he had touched children inappropriately at Sandhill. The suit alleges a 14-year-old who Martinez allegedly took to his home became pregnant, and it says another girl engaged in self-harm amid sustained sexual abuse. The filing notes Martinez “left the facility that April,” language in the complaint that places his departure in the spring following the alleged abuse.

The lawsuit names as defendants Sergio Martinez, the Sandhill Center, the center’s management company and the center’s founder; the complaint also alleges at least three staff members were involved in abusing girls, though only Martinez is specifically named. Plaintiffs allege institutional failures at Sandhill, saying the center was understaffed and more focused on profits from enrollment than on child safety, and they contend the New Mexico Children, Youth and Families Department had awareness of issues at Sandhill and allowed the abuse to occur. Plaintiffs’ attorneys withheld the parents’ names to protect their child’s privacy; the parents said in a written statement that the trauma their child suffered caused the family “immense distress and heartache.”

The Sandhill Center complaint arrives amid broader scrutiny of residential treatment facilities in New Mexico. The law firm Levy Konigsberg is publicly investigating allegations of sexual abuse at New Mexico residential treatment centers and lists facilities such as Bernalillo Academy, Peak Behavioral Health Services and Mesilla Valley Hospital among those of interest. National and state litigation and oversight actions cited by legal summaries include a New Mexico jury verdict of $485 million on October 12, 2024 in a sexual abuse case that allocated $85 million in compensatory damages and $400 million in punitive damages, and a Senate investigation that reported patterns of misconduct at taxpayer-funded facilities naming companies including Universal Health Services, Acadia Healthcare and Devereux Advanced Behavioral Health.

Reporting on Sandhill has also noted a separate suit, filed earlier this month in state District Court in Santa Fe, alleging excessive physical restraint and other mistreatment of a 9-year-old boy during a 2022 stay at a Los Lunas center; that complaint appears to be a separate action from the sexual-abuse filing. The sexual-abuse complaint filed March 5, 2026 remains pending in First Judicial District Court, setting the stage for discovery that could reveal personnel records, the identities of the management company and founder named in the suit, and whether any criminal investigations followed the incidents alleged from 2006 through 2009.