The Supreme Court of the United States has held that a state may exclude aliens from deputy probation officer positions which involve the exercise of the sovereign police power.
Cabell v. Chavez-Salido, 102 S. Ct. 735 (1982).
Deborah C. Phillips,
Constitutional Law - Fourteenth Amendment - Equal Protection - Aliens' Rights - Governmental Function Doctrine,
Duq. L. Rev.
Available at: https://dsc.duq.edu/dlr/vol21/iss1/9