Criminal Case Against Driver in Former LANL Director McMillan's Death Remains Open

Nadia Lopez, 23, faces three petty misdemeanor charges in Los Alamos Municipal Court more than 18 months after her vehicle crossed the centerline on East Road and struck the car driven by former Los Alamos National Laboratory Director Charles McMillan, yet the case has not advanced past pre-trial conference stage as of late March 2026.

The collision occurred in the early morning hours of September 6, 2024, on East Road, 543 feet west of Camino Entrada, as McMillan and his wife, Janet, were leaving Los Alamos. The 293-page Los Alamos Police Department investigation concluded that Lopez's vehicle crossed the center line into oncoming traffic and that there was no driver error on McMillan's part. McMillan, a physicist who directed the laboratory from 2011 to 2017, died from his injuries at Los Alamos Medical Center.

The First Judicial District Attorney's Office determined there was insufficient evidence to support a felony vehicular homicide by reckless driving charge. Three petty misdemeanor counts were filed June 9, 2025, in Los Alamos Magistrate Court: speeding at 11 to 15 mph over the limit, careless driving for failure to give full time and attention, and failure to maintain a traffic lane. Lopez was arraigned July 8, 2025, and pleaded not guilty to all three.

The case then shifted courts. On July 31, 2025, the Los Alamos Police Department dismissed all charges without prejudice in Magistrate Court, and the counts were refiled in Los Alamos Municipal Court, where they now sit before Municipal Judge Elizabeth Allen.

Since that refiling, pre-trial conferences have been placed on the docket for October, November, and December 2025, and again for January, February, and twice in March 2026. Each time, either prosecutor Biagianti Smith or defense attorney Bill Snowden requested a continuance, and Judge Allen granted it. The pattern has drawn pointed questions from community members about the pace of prosecution in a case involving a fatal crash on a primary county roadway.

The next step in the proceeding will hinge on whether the parties reach a plea agreement or proceed to trial on the three petty misdemeanor counts.

McMillan's death amplified existing concerns about safety on Los Alamos corridors. His crash came within months of the death of LANL chemist Philip Leonard in a three-vehicle collision on N.M. 501. A road safety audit produced by the Texas A&M Transportation Institute, with field work conducted in July 2025, identified lane departures as the primary cause of crashes along the N.M. 502 corridor. Crash data covering Los Alamos since 2020 show that center-line crossovers have been a factor in four of the six traffic fatalities recorded in that period.

Case records for the Lopez proceeding are searchable by name through the New Mexico Courts public portal at caselookup.nmcourts.gov. The Los Alamos Municipal Court, located at 2500 Trinity Drive, can be reached at 505-662-8025. Traffic safety concerns on county roads can be directed to the Los Alamos Police Department or to the county's Traffic and Streets Division.