delivered the opinion of the court:
In this appeal, we decide whether unlawful discrimination based on “marital status” under the Illinois Human Rights Act (775 ILCS 5/1 — 101 et seq. (West 1992)) includes no-spouse policies in the workplace. Petitioners, Jim and Colleen Boaden (Jim and Colleen), are employed as Illinois State Police troopers. Jim and Colleen are employed by respondents, the Illinois Department of Law Enforcement, State Police.1 When Jim and Colleen announced their intention to marry one another, they were informed that an unwritten policy prohibited married couples from working on the same shift in the same patrol area. Jim and Colleen subsequently filed charges with the Department of Human Rights alleging unlawful discrimination based on marital status. An administrative law judge sustained the charges and recommended an award of damages and attorney fees.
The State Police filed exceptions to the recommended order with the Commission. The State Police contended that marital status discrimination does not include discrimination based on the identity of one’s spouse. Relying on the recent case of River Bend Community Unit School District No. 2 v. Illinois Human Rights Comm’n, 232 Ill. App. 3d 838 (1992), the Commission concluded that marital status discrimination includes discrimination based on the identity of one’s spouse. However, the Commission reversed the award of damages and attorney fees. The Commission found that no unlawful discrimination occurred because the changes to Jim and Colleen’s employment did not affect terms or conditions of employment that are cognizable under the Act.
Jim and Colleen sought review of the Human Rights Commission decision in the appellate court. The appellate court confirmed the decision of the Commission, but on different grounds. 267 Ill. App. 3d 645. The appellate court concluded that marital status discrimination under the Illinois Human Rights Act does not include employment policies based on the identity of a person’s spouse. 267 Ill. App. 3d at 652. In so finding, the fourth district of the appellate court expressly rejected the contrary conclusion reached by the third district in River Bend. We granted Jim and Colleen’s petition for leave to appeal. 145 Ill. 2d R. 315. We affirm.
Background
The Illinois State Police is organized into a number of districts. Each district is composed of smaller patrol areas, which are patrolled by a three-person squad. Each member of the squad patrols in a separate police car. The three-person squads are replaced at eight-hour intervals.
Colleen was hired to serve as a state trooper in 1982, being initially assigned to the Sangamon County patrol area. In January 1984, Colleen was granted a transfer to the Christian County patrol area. After her transfer, Colleen was assigned to work in the same three-person squad as Jim. After a period of time, Jim and Colleen became romantically involved and decided to marry.
In May 1984, Jim and Colleen informed their supervisor of their plans to marry. Jim and Colleen were informed that an unwritten policy existed which prohibited spouses from working in the same shift in the same patrol area. Jim and Colleen were presented with several options. They could remain in the same patrol area, but on different shifts. Alternatively, Jim could transfer to the Sangamon County patrol area, but work the same hours with the same days off as Colleen. Jim chose to work on a different shift in the same patrol area. This change went into effect about one week before Jim and Colleen were married on July 3, 1984. Jim and Colleen were on their honeymoon for most of July.
After they returned, Jim and Colleen met with their supervisors in attempts to reverse the policy prohibiting spouses from working the same shift. On August 16, 1984, Jim and Colleen filed separate charges of marital status discrimination with the Department of Human Rights. The district commanders for the State Patrol discussed the pending action in a meeting held in September 1984. After the meeting, the district commanders decided to rescind the policy prohibiting spouses from working the same shift. Jim and Colleen were again working the same shift in Christian County by mid-October.
After reviewing the charges, the Department of Human Rights filed separate complaints on behalf of Jim and Colleen with the Commission. The cases were consolidated by order of the chief administrative law judge. In response to the allegations, the State Police admitted that a policy had existed that prohibited Jim and Colleen from working the same shift after their marriage, but argued such a policy was beyond the protections of the Illinois Human Rights Act. The State Police argued that the Act only prohibits discrimination based on an individual’s marital status, and therefore does not apply to a policy prohibiting spouses from working together.
The State Police further argued that if such a policy constituted discrimination under the Act, then the policy is a bona fide occupational qualification that is not actionable. In support, the State Police presented the testimony of a district commander, Captain William Jack Ryan. Ryan testified to his belief that married couples should not work together in the State Patrol for safety and operational reasons. Ryan believed that married couples working the same shift may not act objectively in dangerous situations and that their credibility may be questioned in court. Ryan also questioned whether married couples could be effectively disciplined by superiors.
After a public hearing, the administrative law judge issued an interim recommended order and decision. Relying on the Commission’s decision in In re Burton, 13 Ill. Hum. Rts. Comm’n Rep. 246 (1984), the administrative law judge concluded that marital status discrimination under the Human Rights Act includes no-spouse policies. In Burton, the Commission found that such policies constituted discrimination because the policies were based on stereotypical assumptions concerning how married couples interact in the workplace. The administrative law judge similarly rejected the bona fide occupational qualification defense, finding that there was no evidence to support the view that married couples could not adequately perform their duties while working in the same squad.
The administrative law judge found that Jim and Colleen both suffered changes to the terms and conditions of their employment based on their marital status. The changes in Jim’s employment included his shift reassignment. Although Colleen suffered no shift change, the administrative law judge found that she suffered a change in the condition of her employment because she was no longer able to work with Jim. The administrative law judge stated:
"Many people do not particularly care with whom they work. Others care a great deal. But whether there is a concern or not, with whom one works is as much a condition of employment as where and when one works.”
The administrative law judge therefore recommended that the charges be sustained and ordered Jim and Colleen to submit a request for damages, relief, attorney fees, and costs.
A different administrative law judge conducted the hearing on damages. The judge awarded Colleen $1,620.12 for professional counseling and associated medication and travel costs. The judge also awarded $8,100.60 to Colleen and $3,000 to Jim for emotional injury. The judge further awarded Jim and Colleen $12,351.90 for attorney fees and costs.
The State Police filed exceptions to the recommended disposition with the three-member panel of the Commission. The Commission first rejected the argument that marital status discrimination does not include nepotism policies that prohibit spouses from working together. The Commission followed the recently decided case of River Bend Community Unit School District No. 2 v. Human Rights Comm’n, 232 Ill. App. 3d 838 (1992), in which the third district of the appellate court held that marital status discrimination includes such discrimination based on the identity of a spouse.
Despite this ruling, the Commission reversed the award of damages to Jim and Colleen. The Commission determined that Jim and Colleen suffered no discrimination because the right to work with a specific coworker is not a term or condition of employment that is cognizable under the Act. The Commission further reasoned that the options presented to Jim did not force him to change shifts, but merely work in a different patrol area with different coworkers. These changes did not affect "terms, privileges or conditions of employment” such as hours, vacation days or rate of pay. See 775 ILCS 5/2— 102(A) (West 1992). Thus, the Commission concluded there was no violation of the Human Rights Act.
Jim and Colleen sought judicial review of the Commission’s decision in the appellate court. The appellate court confirmed the Commission’s finding that there was no violation of the Human Rights Act, but did so for reasons rejected by the Commission. The appellate court determined that the plain language of the Illinois Human Rights Act only prohibits discrimination based on an individual’s "[mjarital status” which is defined as "the legal status of being married, single, separated, divorced or widowed.” See 775 ILCS 5/1 — 103(J) (West 1992). The appellate court concluded that no-spouse policies were not based on an individual’s marital status, but rather on the identity of the spouse. Therefore, the appellate court held that no-spouse policies did not violate the protections afforded in the Act. In so finding, the appellate court expressly rejected the contrary holding of River Bend, creating a conflict between the third and fourth districts of the appellate court.
We granted Jim and Colleen’s petition for leave to appeal. 145 111. 2d R. 315. The Illinois Human Rights Commission filed a brief as a respondent, supporting the decision of the Commission. We allowed Women Employed and the National Employment Lawyer’s Association to file an amicus curiae brief.
Analysis
Whether marital status discrimination under the Act reaches no-spouse policies in the workplace is an issue of statutory construction and the following principles apply. In interpreting a statute, our objective is to ascertain and give effect to the intent of the legislature. Hernon v. E.W. Corrigan Construction Co., 149 Ill. 2d 190,194 (1992). The most reliable indicator of legislative intent is the language of the statute. People v. Bryant, 128 Ill. 2d 448, 455 (1989). The language of a statute must be given its plain and ordinary meaning. People v. Bole, 155 Ill. 2d 188, 197 (1993). Where the statutory language is clear and unambiguous, we must apply the statute without further aids of statutory construction. Bole, 155 Ill. 2d at 198; People v. Zaremba, 158 Ill. 2d 36, 40 (1994). The construction of a statute is an issue of law and our review is therefore de nova. Vuletich v. United States Steel Corp., 117 Ill. 2d 417, 421 (1987).
The Illinois Human Rights Act provides:
"It is a civil rights violation:
(A) Employers. For any employer to refuse to hire, to segregate, or to act with respect to recruitment, hiring, promotion, renewal of employment, selection for training or apprenticeship, discharge, discipline, tenure or terms, privileges or conditions of employment on the basis of unlawful discrimination or citizenship status.” 775 ILCS 5/2 — 102(A) (West 1992).
The Act defines unlawful discrimination:
" 'Unlawful discrimination’ means discrimination ■ against a person because of his or her race, color, religion, national origin, ancestry, age, sex, marital status, handicap or unfavorable discharge from military service as those terms are defined in this Section.” (Emphasis added.) 775 ILCS 5/1 — 103(Q) (West 1992).
The Act defines marital status:
" 'Marital status’ means the legal status of being married, single, separated, divorced or widowed.” (Emphasis added.) 775 ILCS 5/1 — 103(J) (West 1992). .
We agree with the appellate court below that the statutory definition of marital status discrimination does not encompass policies based on the identity of one’s spouse. As defined under the Act, prohibited marital status discrimination is discrimination based on an individual’s "legal status” as married, single, separated, divorced, or widowed. In our view, a policy prohibiting spouses from working together presents an entirely different kind of harm than discrimination based on an individual’s legal status. In order to find discrimination under these facts, we must consider not only the individual’s legal status, but also that individual’s relationship to a particular employee. Had the legislature intended to reach this kind of conduct, it would have done so in specific and certain terms. See, e.g., Minn. Stat. § 363.01 (West 1991) (" 'Marital Status’ means whether a person is single, married, remarried, divorced, separated, or a surviving spouse and, in employment cases, includes protection against discrimination on the basis of the identity, situation, actions, or beliefs of a spouse or former spouse” (emphasis added)).
We recognize that our interpretation of the Human Rights Act is at odds with that of the Commission. Where based on agency expertise, the interpretation of an ambiguous statute by an agency charged with its administration is generally entitled to deference. Illinois Consolidated Telephone Co. v. Illinois Commerce Comm’n, 95 Ill. 2d 142, 152 (1983). However, the erroneous construction of a statute by an administrative agency is not binding on this court. Illinois Consolidated Telephone Co., 95 Ill. 2d at 153. In addition, our deference to administrative expertise will not serve to license a governmental agency to expand the operation of a statute. Northern Trust Co. v. Bemardi, 115 Ill. 2d 354, 365 (1987). As we find that the statute is not ambiguous, we decline to defer to the Commission’s interpretation.
Jim and Colleen argue that no-spouse policies encourage persons to live together without the benefit of clergy, contrary to accepted public policy. The Commission, relying on the reasoning of Burton, argues that no-spouse policies constitute discrimination because they are based on stereotypical assumptions concerning spousal behavior. We express no opinion concerning whether such nepotism policies are wise or based on sound reasoning. Our role is limited to giving effect to the intent of the legislature as expressed through the plain language of the statute.
Conclusion
We conclude that marital status discrimination under the Illinois Human Rights Act does not encompass no-spouse policies in the workplace. In light of our holding, we need not address whether the identity of a coworker is a term or condition of employment that is recognized under the Act. For the reasons stated, we affirm the judgment of the appellate court.
Affirmed.
JUSTICE HARRISON took no part in the consideration or decision of this case.
At the time the complaint was filed, the respondent was part of the Illinois Department of Law Enforcement. Subsequently, the State Police became a separate department of state government.