OPINION
HILL, Chief Justice.The City of Fort Worth appeals the trial court’s judgment that William E. Harty, John W. Powell, and Gary D. Wigley, the appellees, are police officers as defined in chapter 143, Local Government Code, particularly section 143.003(5); that they were appointed in substantial compliance with chapter 143; and that they are therefore entitled to civil service status as employees of the City of Fort Worth.
The City urges in three points of error that the doctrines of stare decisis, res judica-ta, and collateral estoppel bar retrial of the issue as to whether city park rangers are police officers under chapter 143; that there is no evidence, or, alternatively, insufficient evidence, to support the trial court’s finding that the appellees have status under chapter 143 of the Texas Local Government Code; and that the officers are not police officers within the meaning of chapter 143 as a matter of law.
We reverse and render judgment that the appellees take nothing by their suit because the appellees, as a matter of law, are not police officers within the meaning of chapter 143.
The City argues in point of error number three that as a matter of law the appellees are not police officers within the meaning of chapter 143 of the Texas Local Government Code because they are park rangers and not officers of the Fort Worth Police Department. The appellees sought a declaratory judgment that they are police officers within the meaning of chapter 143.
This court previously determined that park rangers of the City of Fort Worth are not “policemen” as defined by TEX.REV.CIV. STAT.ANN. art. 1269m, § 2,1 and are therefore not entitled to the same civil service protection as members of the Fort Worth Police Department. City of Fort Worth v. Hernandez, 608 S.W.2d 826, 827 (Tex.Civ.App.—Fort Worth 1980), writ refd n.r.e. per curiam, 617 S.W.2d 923 (Tex.1981).
The appellees contend that they are police officers as defined by Texas Local Government Code section 143.003(5), enacted since our opinion in Hernandez, so that Hernandez is no longer applicable.
Prior to 1985, “policeman,” as defined in article 1269m, referred to a member of the police department who met certain requirements. The definition was amended in 1985 to include any member of the police department “or other peace officer” who met the same requirements.2
In 1987, the definition of “policeman” contained in article 1269m was codified, in a nonsubstantive revision process, into section 143.003(5) of the Texas Local Government Code. See TEX.LOC.GOV’T CODE ANN. § 143.003(5) (Vernon 1988). That section defines a “police officer” as “a member of a police department or other peace officer who was appointed in substantial compliance with this chapter or who is entitled to civil service status under Section 143.005, 143.084, or 143.103.” Id.
The appellees urge that since they are peace officers appointed to their positions in substantial compliance with the provisions of the chapter, they are “police officers” as defined by the Code, and are therefore entitled- to the same civil service protection as members of the Fort Worth Police Department.
*778Assuming that the evidence shows that they are in fact peace officers appointed in substantial compliance with the relevant provisions of the chapter, a reading of the unambiguous statute would appear to support the appellees’ position. However, in construing statutes we are not limited to a reading of the statute’s unambiguous language.
Section 311.028 of the Texas Government Code provides that in construing a statute, whether or not the statute is considered ambiguous on its face, a court may consider, among other matters, the legislative history of the statute. TEX.GOV’T CODE ANN. § 311.023 (Vernon 1988). The City has brought us the legislative history of the 1985 amendment of the definition of “policeman” in article 1269m. It is apparent from that history that the purpose of the amendment was to make the definition of “policeman” broad enough to include park rangers and others in the City of Houston who, through amendment of a different portion of the statute, were being given civil service protection equivalent to members of the Houston Police Department. The appellees have not presented any legislative history that differs from that construction of the statute. As we have noted, the definition of “police officer” at section 143.003(5) of the Local Government Code is merely a codification of the definition of “policeman” in article 1269m without any substantive change. See TEX. LOC.GOVT CODE ANN. § 1.001 (Vernon 1988).
Because we know through our examination of the legislative history that the legislature has never amended the statute to include park rangers in cities of the size of the City of Fort Worth within the definition of “police officer,” we hold that the appellees as a matter of law are not police officers as defined by section 143.003(5).
The appellees insist that the provisions of section 143.103(a) of the Texas Local Government Code, which confers civil service status under the chapter to certain park police officers, is applicable to them even though Fort Worth’s population is less than 1.5 million. See id. § 143.103(a).
As noted by the appellees, section 143.-101(a) of the Texas Local Government Code states that “[e]xeept as otherwise provided, this subchapter applies only to a municipality with a population of 1.5 million or more.” Id. § 143.101(a). Section 143.103(a) is located within that subchapter.
The appellees assert that section 143.-103(a) is nonetheless applicable to them because the reference to section 143.103 in the definition of “police officer” in section 143-003(5) falls within the provision “[ejxcept as otherwise provided” so that the population requirement of 1.5 million or more is inapplicable. Inasmuch as we have held that park police in cities of less than 1.5 million are not included within the definition of “police officer” in section 143.003(5), it follows that that section makes no provision that would indicate that the population requirement is inapplicable to the appellees.
We sustain point of error number three. In view of our determination of point of error number three, we need not determine the remainder of the City’s points of error.
We reverse and render judgment that the appellees take nothing by their suit, with all costs charged to the appellees.
. Act of May 15, 1947, 50th Leg., R.S., ch. 325, § 2, 1947 Tex.Gen.Laws 550, 551, amended by Act of May 23, 1957, 55th Leg., R.S., ch. 391, § 1, 1957 Tex.Gen.Laws 1171, 1171, repealed by Act of May 1, 1987, 70th Leg., R.S., ch. 149, § 49(1), 1987 Tex.Gen.Laws 707, 1306-07.
. See Act of May 27, 1985, 69th Leg., R.S., ch. 958, § 21, 1985 Tex.Gen.Laws 3227, 3240-41.