For Immediate Release
March 7, 2026
Public Affairs
909-387-3700
SAN BERNARDINO, CA — On March 2, 2026, Mark Lee Keller, a 45-year-old transient in San Bernardino, pleaded guilty to a felony count of Attempted Criminal Threats after sending a letter threatening to kill San Bernardino County Sheriff Shannon Dicus. Keller received one year in custody, released for credit time served, and placed on Post-Release Community Supervision (PRCS).
The investigation began in August 2025 when Keller mailed a letter containing threats directed at Sheriff Dicus. During the course of the investigation, Keller admitted to authoring the letter and was subsequently arrested and charged with Criminal Threats.
In cases where someone may be experiencing mental health crisis, the Sheriff’s Department’s practice is to refer individuals to any available services such as CARE court where they would be court ordered to receive the necessary treatment and housing support to help them recover, or Laura’s Law, a program that allows for court-ordered outpatient assistance. Unfortunately, strict eligibility criteria and limited capacity often results in people not getting access to those programs.
PRCS can screen individuals and offer services for mental health, housing and other needs, however, participation in those services is voluntary and cannot be mandated.
Sheriff Shannon Dicus emphasized that the case reflects broader challenges facing law enforcement agencies across California.
“Law enforcement regularly encounters people who clearly need treatment and support, yet the current system often leaves limited options to ensure they receive help before situations escalate. I will continue to work with fellow sheriffs, the Board of Supervisors, and the Legislature to address these challenges,” said Sheriff Shannon Dicus.
