menthal v. Board of Medical Examiners, supra, 57 Cal.2d 228, 233.)” (Whittaker v. Superior Court (1968) 68 Cal.2d 357, 367-368 [66 Cal.Rptr. 710, 438 P.2d 358].) Moreover, the burden of demonstrating the invalidity of a classification under this standard rests squarely upon the party who assails it. (Lindsley v. Natural Carbonic Gas Co. (1911) 220 U.S. 61, 78-79 [55 L.Ed. 369, 377-378, 31 S.Ct. 337]; Blumenthal v. Board of Medical Examiners (1962) 57 Cal.2d 228, 233 [18 Cal.Rptr. 501, 368 P.2d 101]; see also Developments in the Law—Equal Protection (1969) 82 Harv.L.Rev. 1065, 1077-1087.)
A more stringent test is applied, however, in cases involving “suspect classifications” or touching on “fundamental interests.” Here the courts adopt “an attitude of active and critical analysis, subjecting the classification to strict scrutiny. (See Shapiro v. Thompson, supra, 394 U.S. 618, 638 [22 L.Ed.2d 600, 617, 89 S.Ct. 1322]; Sherbert v. Verner (1963) 374 U.S. 398, 406 [10 L.Ed.2d 965, 971-972, 83 S.Ct. 1790]; Skinner v. Oklahoma, supra, 316 U.S. 535, 541 [86 L.Ed. 1655, 1660, 62 S.Ct. 1110]; see also Developments in the Law—Equal Protection (1969) 82 Harv.L.Rev. 1065, 1120-1131 [1087-1131].) Under the strict standard applied in such cases, the state bears the burden of establishing not only that it has a compelling interest which justifies the law but that the distinctions drawn by the law are necessary to further its purpose.” (Westbrook v. Mihaly, supra, 2 Cal.3d at pp. 784-785.) (Some italics added.)
The conventional “rational relationship” test is traditionally applied in cases involving occupational licensing, including those concerning the practice of the healing arts. (See Williamson v. Lee Optical Co. (1955) 348 U.S. 483, 488-489 [99 L.Ed. 563, 572-573, 75 S.Ct. 461]; Blumenthal v. Board of Medical Examiners, supra, 57 Cal.2d 228, 232-233; Magan Medical Clinic v. Cal. State Bd. of Medical Examiners (1967) 249 Cal.App.2d 124, 131-132 [57 Cal.Rptr. 256].) Nevertheless, in certain cases involving occupational regulation the more stringent “strict scrutiny” test has been employed. (See, e.g., In re Griffiths (1973) 413 U.S. 717, 718-722 [37 L.Ed.2d 910, 913-916, 93 S.Ct. 2851]; Raffaelli v. Committee of Bar Examiners (1972) 7 Cal.3d 288, 291-294 [10 Cal.Rptr. 896, 496 P.2d 1264, 53 A.L.R.3d 1149]; Sail’er Inn, Inc. v. Kirby (1971) 5 Cal.3d 1, 16-20 [95 Cal.Rptr. 329, 485 P.2d 529, 46 A.L.R.3d 351]; Purdy & Fitzpatrick v. State of California (1969) 71 Cal.2d 566, 579-580 [79 Cal.Rptr. 77, 456 P.2d 645, 38 A.L.R.3d 1194].) Those cases, however, have invariably involved a classification drawn along lines which rendered it “suspect” in constitutional terms—such as national origin or alienage (Griffiths, Raffaelli, and Purdy & Fitzpatrick) or sex (Sail’er Inn). In the instant case, on the other hand, the statutory classification is based upon