OPINION
FLAHERTY, Chief Justice.This is an appeal from an order of Commonwealth Court granting appellees’ motion for a preliminary injunction to enjoin the enforcement of Section 1707-B (the Reed Amendment) of the Education Empowerment Act (EEA), Act 16 of 2000. The act provides that school districts which have performed poorly be identified and assisted by the Department of Education in improving their performance. At issue in this case is whether the Reed Amendment, Section 1707-B, is unconstitutional insofar as it singles out the schools in Harrisburg for special treatment.1
*395The EEA provides, inter alia, that the Secretary of Education shall prepare a list of schools which have a history of low test performance, as defined in the act. After the school districts are notified of their placement on the list,
1) The Department of Education establishes an academic advisory team for each affected district;
2) The affected district establishes a team to work with the academic advisory team to develop an improvement plan which is to be submitted to the department;
3) The department reviews the plan and may approve it or request modifications;
(4) The board of directors of the affected district “shall implement” the approved plan, notwithstanding any other provision of law to the contrary.
Sections 1703-B-1704-B.
If the district fails to realize its goals within three years, and if the Secretary elects not to allow an additional year, the statute provides that such district will be placed under a board of control consisting of the secretary of education or his designee and two residents of a county in which the district is located, who are appointed by the Secretary. Section 1705-B. The board of control assumes all powers and duties conferred by law upon the board of school directors except that it may not levy taxes. When the district has met the goals in its improvement plan and no longer has a history of low performance, control is restored to the board of directors. Sections 1706-B; 1710-B.
However, Section 1707-B provides an exception to this plan. If a school district is “a school district of the second class with a history of low test performance which is coterminous with *396the city of the third class which contains the permanent seat of government,” i.e., if the school district is located in Harrisburg, the secretary is directed not to include the district on the list of schools with low performance, but to immediately certify the district as an “education empowerment district.” However, a 1707-B school district does not come under control of the three-member board of control. Instead, the mayor of the coterminous city, i.e., Harrisburg, appoints a five-member board which serves at the mayor’s pleasure. Also, the mayor, rather than the district, appoints an “education empowerment team” to develop a plan to improve the performance of the district. The department is not required to appoint an academic advisory team to assist the “empowerment” team in developing the improvement plan. Section 1707-B districts, therefore, are treated quite differently from other districts in that other districts are subject to state input and ultimately, state control if their improvement plans are not realized, whereas Section 1707-B districts are immediately placed under the control of the mayor of Harrisburg.
Relying on Art. Ill, Section 82 of the Constitution of Pennsylvania, Commonwealth Court held that “The Reed Amendment,” i.e., that portion of the Education Empowerment Act which exempts Harrisburg from treatment mandated for other school districts, is unconstitutional because it is special legislation.
The various appellants collectively raise two matters on appeal, whether it was error to conclude that the Reed Amendment was a special law within the meaning of Art. Ill of the Constitution of Pennsylvania, and whether it was error to issue a preliminary injunction.
Art. Ill, Section 32 provides, in part:
The General Assembly shall pass no local or special law in any case which has been or can be provided for by general law and specifically the General Assembly shall not pass any local or special law:
1. Regulating the affairs of counties, cities, townships, wards, boroughs or school districts....
*397As this court stated in Haverford Twp. v. Siegle, 346 Pa. 1, 28 A.2d 786, 788 (1942), the proscription against special laws was “adopted for a very simple and understandable purpose — to put an end to the flood of privileged legislation for particular localities and for private purposes which was common in 1873.” Nonetheless, Art. Ill, Section 20 allows the legislature to classify counties, cities, boroughs, school districts and townships according to population and provides that all laws passed with respect to such classes shall be deemed general legislation. As this court stated in Freezer Storage v. Armstrong Cork Co., 476 Pa. 270, 382 A.2d 715, 718 (1978):
The general rule for determining whether an act is a “special law” violating the Pennsylvania Constitution is this:
“Legislation for a class distinguished from a general subject is not special, but general; and classification is a legislative question, subject to judicial revision only so far as to see that it is founded on real distinctions in the subjects classified, and not on artificial or irrelevant ones, used for the purpose of evading the constitutional prohibition. If the distinctions are genuine, the courts cannot declare the classification void, though they may not consider it to be on a sound basis. The test is not wisdom, but good faith in the classification.”
The judicial function, then, with respect to classifications, is “to see that the classification at issue is founded on real distinctions in the subjects classified and not on artificial or irrelevant ones used for the purpose of evading the constitutional prohibition.”2
Plainly, the classification “a school district of the second class with a history of low test performance which is coterminous with the city of the third class which contains the permanent seat of government” merely refers to Harrisburg. However, there is no rational basis for treating the school *398district of Harrisburg differently from other school districts with failed educational systems. Additionally, this court has held that a classification is per se unconstitutional when the class consists of one member and it is impossible or highly unlikely that another can join the class. Harristown Development Corp. v. Dep’t of General Services, 532 Pa. 45, 614 A.2d 1128, 1134 n. 9 (1992). Appellants argue that it is possible that the capital might be moved to another city of the third class which would also meet the other criteria of Section 1707-B, and that the class of cities meeting the criteria of Section 1707-B, therefore, does not consist only of one member. This argument is without merit, for the statute authorizing the location of the capital specifies that there be only one capital city, Act of Feb. 21, 1810, PL 30 § 1. There can, therefore, be no more than one member of the class. Commonwealth Court was correct, therefore, in determining that the Reed Amendment is constitutionally infirm.
The remaining issue, whether Commonwealth Court erred in issuing a preliminary injunction, is moot, for having determined that the lower court was correct in holding the Reed Amendment unconstitutional, any application of the Reed Amendment would have been unlawful and the injunction, which merely prevented the Reed Amendment from being applied, whether it was proper or improper, can have caused no harm. See Cianfrani v. Com. State Retirement Board, 505 Pa. 294, 479 A.2d 468 (1984) (An unconstitutional statute is void ab initio.)
Affirmed.
Justice NEWMAN did not participate in the consideration or decision of this case. Justice NIGRO concurs in the result. Justice SAYLOR files a concurring and dissenting opinion.. On June 1, 2000, the Harrisburg School District and School Board, five members of the Harrisburg School Board, and five district residents filed a petition for review in the nature of a complaint in equity for declaratory relief challenging the constitutionality of Act No. 2000-*39516 (Act 16) and section 8.1 of Act 16 (the Educational Empowerment Act). Respondents were the governor, the secretary of education of Pennsylvania, the mayor of Harrisburg and five Jane Does representing unnamed members of the board of control for the Harrisburg School District. Senator Robert Jubelirer and Representative Matthew Ryan were permitted to intervene in support of the respondents.
Petitioners also filed an application for special relief in the nature of a preliminary injunction to enjoin the implementation of the provisions of Section 1707-B of Section 8.1 of Act 16.
. Accord, Defazio v. Civil Service Commission, 562 Pa. 431, 756 A.2d 1103 (2000) ("The prohibition against treating people differently under the law does not preclude the Commonwealth from resorting to legislative classifications, provided that those classifications are reasonable rather than arbitrary and bear a reasonable relationship to the object of the legislation.")