The appellant is a firefighter employed by the City of Poplar Bluff. On April 5, 1983 he was elected a district director of Butler County Fire Protection District. Compensation is limited by § 321.190, RSMo 1978,1 to an attendance fee not to exceed $30 per meeting. He was ousted of this office by the Circuit Court of Butler County, in an action of quo warranto filed by the prosecuting attorney, pursuant to the following statute:
No person holding any lucrative office or employment under this state, or any political subdivision thereof as defined in section 70.120, RSMo, shall hold the office of fire protection district director under this chapter. When any fire protection district director accepts any office or employment under this state or any political subdivision thereof, his office shall thereby be vacated and he shall thereafter perform no duty and receive no salary or expenses as fire protection district director. This section shall not apply to members of the organized militia, of the reserve corps, public school employees and notaries public. The term ‘lucrative office or employment’ does not include receiving retirement benefits for service rendered to a fire protection district, the state or any political subdivision thereof.
He appeals to this Court arguing, initially, that the City of Poplar Bluff is not a “political subdivision” of the state. He then argues that, if the statute applies to the City of Poplar Bluff, it violates the First Amendment to the Constitution of the United States and the Equal Protection Clause of the Fourteenth Amendment. We have jurisdiction because of the alternate contentions bringing the validity of the statute into question. State ex rel. Union Electric Company v. Public Service Commission of the State of Missouri, et al., 687 S.W.2d 162 (Mo. banc 1985).
The appellant’s first point is easily answered. Section 321.015 explicitly refers to § 70.120, which defines political subdivision as follows:
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‘Political Subdivision’ shall mean any agency or unit of this state which now is, or hereafter shall be, authorized to levy taxes or empowered to cause taxes to be levied;
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We take judicial notice that the City of Poplar Bluff, a third class city with an optional council manager government, is authorized to levy taxes.
We also find that the restrictions on the appellant’s right to hold public office, so long as he remains in his firefighter position, are valid. The First Amendment protects the right to participate in political activity and to seek and hold public office, but political involvements of public employees may be restricted if a sufficient public interest is shown. United Public Workers of America v. Mitchell, 330 U.S. 75, 67 S.Ct. 556, 91 L.Ed. 754 (1947); Pollard v. Bd. of Police Commissioners, 665 S.W.2d 333 (Mo. banc 1984). In determining the sufficiency of the public interest we should first scrutinize the statute in context. In some cases evidence may be necessary or helpful (cf. Pollard, supra), but this is not necessary if the public interest is apparent from the face of the statute. The Attorney *372General is a proper party to assert the public interest when a statute is challenged as unconstitutional, but is not a necessary party. Mo.S.Ct.Rule 52.12(b). We also must make a strong effort to sustain a statute when its constitutionality is challenged. When appropriate public interest is shown, judgments of wisdom and necessity are for the legislature alone.
Public bodies have an important interest in securing the absolute loyalty of their employees. Different governmental units frequently interrelate. See Missouri Constitution, Art. VI, sec. 16; § 70.220, RSMo 1978. The Legislature well might conclude that an employee of one governmental unit should not be eligible to serve as a member of the governing board of another. Given this conclusion, there is no less restrictive alternative. In the appellant’s situation the possibility of conflict is clear. He might be reluctant to approve as director a contract or agreement which would affect his duties as firefighter. If it need be shown that the public interest is compelling, we conclude that the test has been met.
The equal protection argument likewise fails. The exemptions refer to types of employment which are customarily part time, except for the exemption of “public school employees.” The legislature might appropriately conclude that public school employees are isolated from the normal course of political activity so that the possibility of conflict is minimal. A person in the position of the appellant is not normally permitted to assert unconstitutionality simply because others are exempted from a statutory disability which applies to him. See Otten v. Schicker, 655 F.2d 142, 146 (8th Cir.1981), affirming 492 F.Supp. 455, 459 (E.D.Mo.1980), which holds that a police officer is not denied equal protection simply because restrictions on his political activities are not likewise imposed on firefighters.
The judgment is affirmed.
RENDLEN, C.J., and WELLIVER, HIGGINS, GUNN and BILLINGS, JJ., concur. DONNELLY, J., dissents in separate opinion filed.. Section 321.015, RSMo 1978 was amended effective August 13, 1984 to exclude fire protection districts in second, third and fourth class counties. Counsel did not call this amendment to our attention. Appellant was elected to office April 5, 1983. Ouster, in an action of quo war-ranto, occurred April 4, 1984. Because ouster occurred prior to the statutory amendment, the Circuit Court was correct in its ruling. The general rule is that an officer must be qualified to hold office on the day his duties begin. Removal of a disqualification after duties have commenced does not entitle a person to remain in office. State v. Gray, 360 S.W.2d 642 (Mo.1962), 67 C.J.S., Officers, § 45.