What is the test for establishing prima facie existence of a conspiracy?

evidence to establish the prima facie existence of a conspiracy. ( People v. Hardy (1992) 2 Cal.4th 86, 139, 5 Cal.Rptr.2d 796, 825 P.2d 781.) "Once independent proof of a conspiracy has been shown, three preliminary facts must be established: (1) that the declarant was participating in a conspiracy at the time of the declaration; (2) that the declaration was in furtherance of the objective of that conspiracy; and (3) that at the time of the declaration the party against whom the evidence is offered was participating or would later participate in the conspiracy. " ( Ibid. )