What is the test for judicial review of the powers of the California Civil Service Commission?

'The Commission has wide discretionary powers in many of its fields of operation. However, such commissions have only such powers as are conferred upon them. When they exceed or abuse their powers it is not only within the power, but it is the duty of the judicial branch of the government to prevent such excess or abuse upon the petition of those adversely affected.' Allen v. McKinley, 18 Cal.2d 697, 705, 117 P.2d 342, 347.

'Moreover, with particular reference to the administration of civil service, it is the policy of the courts of this state that 'Courts should let administrative boards and officers work out their problems with as little judicial interference as possible. * * * Such boards are vested with a high discretion, and its abuse must appear very clearly before the courts will interfere.' (Citations.') Nelson v. Dean, 27 Cal.2d 873, 881, 168 P.2d 16, 21, 168 A.L.R. 467.