On August 18, 2022, at 1035 Pacific daylight time, a Cessna 195, N1097D, sustained substantial damage when it was involved in an accident near El Cajon, California. The pilot sustained serious injuries. The airplane was operated as a Title 14 Code of Federal Regulations Part 91 personal flight. The pilot reported that the airplane had recently undergone maintenance. The mechanic performing the maintenance stated that he removed the right wing as part of a repair. He additionally drained all the fuel from both wings to enable him to re-seal both wings’ fuel sending units. The pilot further stated that after completing the maintenance, the mechanic told him that he added the fuel back in the wings, adding about seven gallons in each tank. The pilot did not add any additional fuel. The pilot added that the accident flight was the first flight after the maintenance. He intended to depart Gillespie Field, San Diego, California, and stay in the traffic pattern. At 1023, the airplane departed from runway 27R. At 1033 the pilot declared an emergency to air traffic control stating he had experienced a full electrical failure. He maneuvered the airplane back toward the runway and the engine suddenly stopped producing power. He attempted to restart the engine to no avail. He made an off-airport landing on a freeway and the airplane came to rest adjacent to an onramp, about three-miles short of the runway. The recovery personnel stated that they recovered about 3-3.5 gallons of fuel at the accident site. The Federal Aviation Administration inspector stated that there was no fuel leakage at the accident site. The pilot stated that although he checked the quantity on the fuel gauges, they were erroneous. He did not verify the quantity by doing a visual check of the actual fuel on board. He reported that the mechanic had stolen the fuel and didn’t add it back to the wing tanks. The pilot reported no preimpact mechanical malfunctions or failures with the airplane that would have precluded normal operation.