A staff member for a Democratic California lawmaker remains in federal custody after immigration authorities arrested him at a Las Vegas airport, prompting demands for his release from elected officials in San Francisco.
Ho-Yin Mo, a field representative for California Assemblywoman Catherine Stefani, was arrested by federal agents at Harry Reid International Airport on Sept. 17 during what the Department of Homeland Security described as a targeted immigration enforcement operation.
Mo, a Hong Kong native and former television journalist in San Francisco, was subsequently taken to the Nevada Southern Detention Center in Pahrump.
DHS says Mo legally entered the United States on Jan. 13, 2020, but remained in the country beyond the expiration of his authorized stay on May 15 of that year.
“Mo lawfully entered the U.S. on a temporary basis but illegally overstayed his welcome,” DHS said.
The department also disputed suggestions that Mo’s authorization to work for the California Legislature established that he currently has lawful immigration status.
“Work authorization or a pending application do NOT confer legal status in the United States,” DHS said.
Mo’s attorney, Kevin Lo, has provided additional context about his immigration case.
Lo told the San Francisco Chronicle that Mo applied for asylum in 2023 and that the application remains pending.
He said Mo possesses a valid employment authorization document allowing him to legally work in the United States while the asylum application is being considered.
Employment authorization and immigration status are legally distinct issues. Certain immigrants with pending applications can receive permission to work while their underlying immigration cases remain unresolved.
Mo has not been publicly accused of committing a criminal offense in connection with his arrest. His detention instead stems from an alleged immigration violation and the resulting removal proceedings.
Stefani has called for her employee’s release.
“My message today is simple: I am respectfully calling for Ho Yin Mo’s release as soon as possible,” she said.
Stefani described Mo as an important member of her district staff who helps residents navigate government services.
According to the assemblywoman, Mo assists constituents seeking health care coverage, child care, food assistance and other services and serves as a liaison to Chinese-American communities in her district.
“Our whole community eagerly awaits Ho Yin’s return to his home and his job where he is loved and adored,” Stefani said.
Mo joined Stefani’s district office in January 2025.
Before entering state government, he worked on Asian American and Pacific Islander outreach during former San Francisco Mayor London Breed’s unsuccessful 2024 reelection campaign.
He previously worked as an anchor and reporter for KTSF Channel 26, a Chinese-language television station serving the San Francisco Bay Area.
His broadcasting career made him a recognizable figure among the region’s Chinese-speaking population.
Stefani represents California’s 19th Assembly District, which includes western San Francisco and northern San Mateo County.
She previously served on the San Francisco Board of Supervisors from 2018 until joining the state Assembly in 2024.
Federal officials have defended Mo’s arrest despite his position with a state legislator.
“No one is above the law, not even the California legislature and its staff,” First Assistant U.S. Attorney Bill Essayli wrote on social media following the arrest.
DHS also linked the case to the Trump administration’s broader immigration enforcement policies at airports.
The department says the administration has reversed policies that allowed some people without lawful immigration status to use domestic air travel while their cases were unresolved.
“This administration is working diligently to ensure that aliens in our country illegally can no longer fly unless it is out of our country to self-deport,” DHS said.
The Transportation Security Administration has separately tightened identification requirements for some travelers without conventional identification documents as the administration expands cooperation between federal agencies on immigration enforcement.
Mo’s case highlights a distinction that has become central to the dispute.
Stefani emphasizes that Mo has federal authorization to work and a pending immigration case.
This article may contain commentary which reflects the author's opinion.
