Santa Rosa Man Arrested for the Alleged Illegal Manufacturing of Firearms
SANTA ROSA, CA — “Recently, detectives with the Santa Rosa Police Department (SRPD) Property Crimes Investigations Team (PCI) have been investigating Joshua Penuelas, a 22-year-old resident of Cloverdale, for suspected illegal firearms manufacturing and sales. On February 10, 2026, detectives with PCI and the SRPD Narcotics Investigations Team arrested Penuelas following a traffic stop and served search warrants on two residences believed to be associated with Penuelas and his firearms manufacturing operation.
At approximately 5:15 a.m., detectives in a marked SRPD patrol car conducted a traffic stop on a vehicle in which Penuelas was observed as a passenger. Penuelas was detained without incident. Detectives discovered Penuelas was in possession of a loaded handgun concealed in his waistband at the time of the traffic stop.
At approximately 5:20 a.m., detectives served a search warrant at a residence located in the 100 block of Garden Circle, Cloverdale, in which Penuelas resides part-time. An adult female and a young child also reside at this residence. Detectives located 36 firearms, many of which were loaded, unsecured, and easily accessible to the child. In addition to the firearms, detectives located numerous privately manufactured high-capacity magazines, a 3D printer, and printing materials believed to be associated with the illegal manufacturing of firearms. At the conclusion of the search warrant and following the removal of the firearms, the child was able to remain in the custody of the adult female.
At approximately 5:45 a.m., detectives served a search warrant at the residence of a relative of Penuelas, located in the 100 block of Treadway Court, Cloverdale. Penuelas lived at this residence part-time as well. During the service of the search warrant, detectives located numerous firearms, privately manufactured high-capacity magazines, two 3D printers, printing materials, and a laptop believed to be associated with the illegal manufacturing of firearms.
At both locations, the recovered firearms included assault weapons and handguns that were either complete in build or in various stages of completion. In total, the SRPD PCI team recovered three 3D printers, more than 20 high-capacity magazines, 10 assault weapons, and 157 handguns, many of which included only the lower receiver. In California, a lower receiver is legally considered a firearm because California law explicitly includes the frame or receiver of a weapon in its definition of a “firearm.” Under 16520 PC, California defines a firearm to include “the frame or receiver of any” pistol, rifle, or shotgun. A firearm can be fully rebuilt around a serialized receiver, even if all other parts are replaced. By controlling the core component, the law prevents untracked firearm manufacturing and ensures background checks apply to the essential part needed to create a working gun.
Penuelas was arrested and booked into Sonoma County Main Adult Detention Facility for the following offenses:
25850(a) PC – Possession of a loaded firearm in public
25400(a)(2) PC – Possession of a concealed firearm
30600(a) PC (10 counts) – Manufacturing and sales of assault weapons
30605 PC (10 counts) – Possession of assault weapon
32310(a) PC (17 counts) – Manufacturing of high-capacity magazines
23900 PC (150+ counts) – Possession of a firearm with an obliterated serial number
273a(A) PC – Felony child endangerment
29180(b) PC (150+ counts) – Manufacture firearm without a serial number
29010 PC – Used a 3D printer to manufacture firearms
The Property Crimes Investigations Team is made up of five undercover detectives and a sergeant who investigate serious offenses such as major thefts, burglaries, fraud, identity theft, arson, firearms trafficking, environmental crimes, and financial exploitation of elderly victims. They specialize in complex cases that require detailed, focused investigative work. In 2025, SRPD PCI conducted numerous firearms trafficking, sales, and illegal manufacturing investigations, resulting in the seizure of 88 illegally possessed firearms. Many of which were privately manufactured firearms, commonly known as ‘ghost guns,’ which are unserialized and untraceable.
The dismantling of this illegal firearms manufacturing operation reflects SRPD’s commitment to reducing violence through data‑driven strategies, innovative investigative techniques, and the strategic deployment of specialized resources. These efforts directly support Chief John Cregan’s top organizational priority of preventing violent crime by targeting the individuals and networks that drive it. SRPD remains dedicated to enhancing safety throughout Santa Rosa and the region by removing illegally manufactured firearms from circulation and ensuring those responsible are held fully accountable.
Santa Rosa Police Department case number 26-1445.”
