Is hearsay sufficient to satisfy the preponderance of the evidence standard?

I do not doubt that evidence, whether hearsay or not, that is unreliable and uncorroborated cannot satisfy the preponderance-of-the-evidence standard. It might also violate due process to base a finding on unreliable and uncorroborated evidence. Ultimately, this case comes down to a simple question of whether substantial evidence supports the trial court's jurisdictional finding. If not, section 355's preponderance-of-the-evidence requirement makes it invalid. As with all factual questions, the trial court makes the initial finding, and reviewing courts review those findings deferentially. (See, e.g., People v. Johnson (1980) 26 Cal.3d 557, 578, 162 Cal.Rptr. 431, 606 P.2d 738.)