A Dec. 6, 2016, file photo provided by the City of Oakland shows inside the burned warehouse after the deadly fire that broke out Dec. 2, 2016, in Oakland, Calif. Deaths from California fires on the scuba diving boat Conception and at the so-called Ghost Ship warehouse have brought a search for blame aimed at finding whether someone was negligent. Getting criminal charges to stick in the 2016 fire at the Ghost Ship warehouse has proven difficult and could provide lessons as investigators decide whether a crime occurred aboard the Conception scuba diving boat that burned Sept. 2, 2019. (City of Oakland via AP, File)