The Cal Fire engineer behind bars on suspicion of intentionally starting several brush fires in Sonoma County was previously an inmate firefighter. Prosecutors say Robert Hernandez spent months as an inmate firefighter after being convicted of causing a deadly collision in San Bernardino in 2016. The California Department of Corrections and Rehabilitation confirms Hernandez was in a conservation camp program for eight months while serving prison time in 2018. Hernandez, who was living in Healdsburg, is accused of setting fires near Healdsburg, Geyserville and Windsor in recent weeks. The fires date back to August 15th.