delivered the opinion of the Court.
The sole issue in this appeal is whether the evidence is sufficient to support the trial court’s finding that the accused was operating a motor vehicle while intoxicated.
Falls Church (the city) adopted an ordinance effective July 1, 1989, which incorporated by reference into the city code the provisions of Code §§ 18.2-266, et seq. and 46.1-168, et seq. that pertained to “driving motor vehicles while intoxicated.”1 The parties stipulated that:
1. On July 6, 1989, in the early morning hours, Officer B.R. Darden of the Falls Church City Police Department found the Defendant [John T. Stevenson] inside of a motor vehicle asleep, behind the steering wheel. The vehicle was located on a 7-11 parking lot in the City of Falls Church. The key was in the ignition but it was not recalled whether the key was in the “on” or “off’ position. The engine of the motor vehicle, and all of its other mechanical and electrical parts were off.
2. It was not known how the motor vehicle arrived at the parking lot, and how long it had been at that location.
*4363. Officer Darden awoke the Defendant, at which time it became apparent to her that he was intoxicated, and Defendant stipulated that he was intoxicated at that time. She then placed him under arrest and subsequently obtained a warrant [that charged Stevenson with a violation of the City of Falls Church drunk driving ordinance].
Upon his conviction of drunk driving by the general district court, Stevenson appealed to the Circuit Court of Arlington County. In a bench trial, that court also found him guilty, and Stevenson appealed to the Court of Appeals. In an unpublished opinion, the Court of Appeals affirmed the circuit court, holding that Stevenson was the “operator” of his car within the proscription of Code § 18.2-266 because he was “in actual physical control of the motor vehicle.”
Initially, we review several well-established legal principles before considering Stevenson’s argument that the proof is insufficient to establish his “actual physical control of a motor vehicle” within the meaning of Code § 46.1-1(17). Those principles are:
Penal statutes are to be strictly construed against the Commonwealth and in favor of the citizen’s liberty. . . . Such statutes may not be extended by implication; they must be applied to cases clearly described by the language used. . . . And the accused is entitled to the benefit of any reasonable doubt about the construction of a criminal statute.
Martin v. Commonwealth, 224 Va. 298, 300-301, 295 S.E.2d 890, 892 (1982) (citations omitted). And, those principles apply to our constructions of penal ordinances. See Rollins v. Town of Gordonsville, 216 Va. 25, 26, 215 S.E.2d 637, 638 (1975).
On brief, the city argues that this Court has not adopted “a bright line test that requires some part of the car to be in motion — either the key to be turned ‘on’, wires being connected, or some other action like putting the car in gear.” Expanding upon this, the city contends that:
It does not matter whether the motor is running or idle nor whether the drunk is in the front seat or the back seat. His potentiality for harm is lessened but not obviated by a silent motor or a back seat position, provided, of course, he is the one in control of the car. It takes only a flick of the wrist to *437start the motor or engage the gears, and it requires only a moment of time to get under the wheel from the back seat. A drunk in control of the motor vehicle has such a propensity to cause harm that the statute intended to make it criminal for him to be in a position to do so.
Thus, according to the city, if an intoxicated defendant is in the car with the means of starting the engine, or of operating its mechanical or electrical equipment, he is “in actual physical control of a vehicle” and, therefore, is its operator within the meaning of the Falls Church drunk driving ordinance. In essence, the city invites us to apply a part of the definitional language of Code § 46.1-1(17) disassociated from the ordinary meaning of the words “operator” or “driver.” We decline the invitation.
Instead, we construe the words “operator” and “driver” in the statute according to their ordinary meaning, given the context in which they were used. Grant v. Commonwealth, 223 Va. 680, 684, 292 S.E.2d 348, 350 (1982). An “operator” is defined in pertinent part as “one that produces a physical effect or engages himself in the mechanical aspect of any process or activity: as . . . one that uses or operates a machine or device . . . sometimes used to distinguish the user of fixed devices from the driver of automotive devices.” Webster’s Third New International Dictionary 1581 (1986). A “driver” is defined in pertinent part as “one that drives something: as . . .a person in actual physical control of a vehicle (as an automobile)." Id. at 692, 292 S.E.2d at 348 (emphasis added).
And, we have applied the ordinary meaning of these two words in our constructions of Code §§ 18.2-266 and 46.1-1(17). In three cases, we have held that a vehicle occupant was in “actual physical control” of the vehicle within the meaning of Code § 46.1-1(17) when he was seated behind the steering wheel and performed certain acts. Williams v. City of Petersburg, 216 Va. 297, 301, 217 S.E.2d 893, 896 (1975) (ran engine and made “motion” to gearshift); Nicolls v. Commonwealth, 212 Va. 257, 258, 184 S.E.2d 9, 10 (1971) (activated headlights and heater and ran engine with car in high gear but lack of fluid in transmission made car inoperable); Gallagher v. Commonwealth, 205 Va. 666, 670, 139 S.E.2d 37, 38 (1964) (accelerated engine with car in gear although car immobile because stuck in ditch).2
*438In Williams, quoting Gallagher, we pointed out that “operating” a vehicle within the proscription of the drunk driving statute
not only includes the process of moving the vehicle from one place to another, but also includes starting the engine, or manipulating the mechanical or electrical equipment of the vehicle without actually putting the car in motion. It means engaging the machinery of the vehicle which alone, or in sequence, will activate the motive power of the vehicle.
Id. at 300, 217 S.E.2d at 896 (emphasis added) (citation omitted). As we said in affirming the Williams conviction:
From all of these facts [the motor of the car was running, upon being aroused, the defendant made a “motion” to the gearshift], the trial court could properly find beyond a reasonable doubt that the defendant was in actual physical control of the vehicle and that he had engaged the machinery of the vehicle which alone, or in sequence, would have activated its motive power. Therefore, the defendant was “operating” the vehicle within the meaning of the ordinance.
Id. at 301, 217 S.E.2d at 896.
We adhere to our holding in Williams and apply it here. It was “not recalled whether the key was in the ‘on’ or ‘off’ position.” And, on appeal, we must assume that the key was in the off position.
Because the presence of the key in the ignition switch in the off position did not engage the mechanical or electrical equipment of Stevenson’s car, Stevenson did not “drive or operate” the car within the meaning of the statutes that were incorporated by reference in the Falls Church ordinance.
Accordingly, we will reverse the judgment of the Court of Appeals affirming the conviction, dismiss the warrant, and enter final judgment for the defendant.
Reversed and final judgment.
On July 1, 1989, Code § 18.2-266 provided (and still provides) in pertinent part that “[i]t shall be unlawful for any person to drive or operate any motor vehicle . . . while such person is under the influence of any . . . self-administered intoxicant.” (Emphasis added.)
On July 1, 1989, Code § 46.1-1(17), in pertinent part, defined a vehicle “[ojperator” or “driver” as “[e]very person who either (i) drives or is in actual physical control of a motor vehicle upon a highway.” By an amendment effective October 1, 1989, that definition was recodified as a part of the definitions in Code § 46.2-100. Acts 1989, c. 727.
Lyons v. Petersburg, 221 Va. 10, 266 S.E.2d 880 (1980), has little to do with the issue in this case. Here, we are concerned with the issue of the extent of the accused’s activity *438necessary to constitute “actual physical control” of a vehicle. Lyons deals with the sufficiency of the circumstantial evidence necessary to establish that an accused had driven his vehicle into a parked car.