What is the probationary period for a probationary appointee?

The early probationary appointments were for a single definite time and, in People ex rel. Kastor v. Kearny (supra, (164 N.Y.) p. 66 (587 N.E. 15)), it was pointed out that a probationary term; "is not 'any time' within a fixed period of duration, unmeasured by the rules, and measureable by the pleasure or will of the appointing power. Probation or probationary implies the purpose of the term or period, but not its length; the rules could fix its length, for so the statute provides." The court went on to explain (p. 67 (, 58 N.E. 15)) that, during the probationary period, the probationary appointee was not to be peremptorily discharged . . .

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