There are two prongs to the test for the beneficial interest required to pursue an action in mandamus. The first, as noted in Parker v. Bowron, supra, 40 Cal. 2d at page 351, is whether the plaintiff will obtain some benefit from issuance of the writ or suffer some detriment from its denial. The plaintiff's interest must be direct (ibid.; see also Ellis v. Workman (1904) 144 Cal. 113, 115 77 P. 822), and it must be substantial. (Braude v. City of Los Angeles (1990) 226 Cal. App. 3d 83, 87 276 Cal. Rptr. 256.) Also, it generally must be special in the sense that it is over and above the interest held in common by the public at large. (Tobe v. City of Santa Ana (1995) 9 Cal. 4th 1069, 1085-1086 40 Cal. Rptr. 2d 402, 892 P.2d 1145.) The second prong of the beneficial interest test is whether the interest the plaintiff seeks to advance is within the zone of interests to be protected or regulated by the legal duty asserted. See United States v. SCRAP (1973) 412 U.S. 669, 686 93 S. Ct. 2405, 2415, 37 L. Ed. 2d 254, 269; Sierra Club v. Morton (1972) 405 U.S. 727, 733 92 S. Ct. 1361, 1365, 31 L. Ed. 2d 636, 642; Data Processing Service v. Camp (1970) 397 U.S. 150, 153 90 S. Ct. 827, 829-830, 25 L. Ed. 2d 184, 188.)