TORONTO CRIMINAL and DUI LAWYERS
FAQ - DUI - Impaired
What is Impaired?
1. What is "Operation While Impaired"?
Operation while impaired is defined as operating a conveyance while the person’s ability to operate the conveyance is impaired to any degree by alcohol or a drug or by a combination of alcohol and a drug.¹
¹ “Criminal Code, RSC 1985, c C-46”
(26 May 2026) https://www.canlii.org/en/ca/laws/stat/rsc-1985-c-c-46/latest/rsc-1985-c-c-46.html (accessed 17 July 2026) at s 320.14(1)(a).
2. What is a “Conveyance” in this Context?
A conveyance is defined as a motor vehicle, a vessel, an aircraft, or railway equipment.² A motor vehicle is defined as a vehicle that is drawn, propelled or driven by any means other than muscular power, but does not include railway equipment.³
² “Criminal Code, RSC 1985, c C-46”
(26 May 2026) https://www.canlii.org/en/ca/laws/stat/rsc-1985-c-c-46/latest/rsc-1985-c-c-46.html (accessed 17 July 2026) at s 320.11.
³ “Criminal Code, RSC 1985, c C-46”
(26 May 2026) https://www.canlii.org/en/ca/laws/stat/rsc-1985-c-c-46/latest/rsc-1985-c-c-46.html (accessed 17 July 2026) at s 2.
3. What is “Operation” in this Context?
To operate is defined as, in respect of a motor vehicle, to drive the motor vehicle or to have care or control of the motor vehicle.⁴
⁴ “Criminal Code, RSC 1985, c C-46”
(26 May 2026) https://www.canlii.org/en/ca/laws/stat/rsc-1985-c-c-46/latest/rsc-1985-c-c-46.html (accessed 17 July 2026) at s 320.11
4. What are the Essential Elements of "Operation While Impaired"?
The essential elements of "Operation While Impaired" have been defined as
1. That the accused operated a conveyance⁵
2. While the accused’s ability to operate the conveyance was impaired to any degree by alcohol or a drug or by a combination of alcohol and a drug.⁶
⁵ “Criminal Code, RSC 1985, c C-46”
(26 May 2026) https://www.canlii.org/en/ca/laws/stat/rsc-1985-c-c-46/latest/rsc-1985-c-c-46.html (accessed 17 July 2026) at s 320.14(1)(a).
⁶ “Criminal Code, RSC 1985, c C-46”
(26 May 2026) https://www.canlii.org/en/ca/laws/stat/rsc-1985-c-c-46/latest/rsc-1985-c-c-46.html (accessed 17 July 2026) at s 320.14(1)(a).
5. What are the Actus Reus (the act) and the Mens Rea (the mental state) of "Operation While Impaired"?
The actus reus for impaired operation of a conveyance is the act of operating a conveyance when the voluntary consumption of alcohol or drug has impaired the accused’s ability to operate the motor vehicle, and the mens rea for impaired operation of a conveyance is the intent to operate a motor vehicle after voluntarily consuming alcohol or a drug.⁷
⁷ Cf, “R. v. Castelblanco Velasco, 2019 ONCJ 84 (CanLII)”
https://www.canlii.org/en/on/oncj/doc/2019/2019oncj84/2019oncj84.html (accessed 17 July 2026) at para 115.
6. How severe must the impairment of the accused’s ability to operate the conveyance be in order for the accused to be convicted of impaired operation?
Whether an accused was impaired while operating a conveyance is essentially a question of fact which a trier of fact must determine based upon the evidence.⁸
Before convicting an accused of impaired operation, the trial judge must be satisfied that the accused's ability to operate a motor vehicle was impaired by alcohol or a drug, and if the evidence of impairment establishes any degree of impairment ranging from slight to great, the offence of impaired operation has been made out.⁹ If the ability to operate a motor vehicle is impaired (even slightly) by alcohol or drugs, it is not necessary that the degree of that impairment be marked.¹⁰ But the Courts must not fail to recognize the fine but crucial distinction between slight impairment generally and slight impairment of a person’s ability to operate a motor vehicle.¹¹ It is a misinterpretation of the jurisprudence to read the jurisprudence as requiring only proof of a slight degree of impairment by alcohol or a drug as opposed to a slight degree of impairment of one’s ability to operate a motor vehicle as a result of the consumption of alcohol or a drug.¹²
The impairment of an accused’s ability to operate a conveyance is generally understood as meaning the alteration of one’s judgment and the decrease in one’s physical abilities.¹³
Before a trier of fact can make a finding of guilt about a charge of operation while impaired, the trier of fact must be satisfied beyond a reasonable doubt that the accused’s ability to operate a conveyance was impaired to some degree by alcohol and/or a drug.¹⁴
⁸ Cf, “R. v. Castelblanco Velasco, 2019 ONCJ 84 (CanLII)”
https://www.canlii.org/en/on/oncj/doc/2019/2019oncj84/2019oncj84.html (accessed 17 July 2026) at para 116.
⁹ “R. v. Stellato, 1993 CanLII 3375 (ON CA)”
https://www.canlii.org/en/on/onca/doc/1993/1993canlii3375/1993canlii3375.html (accessed 19 July 2026).
¹⁰ “R. v. Andrews, 1996 ABCA 23 (CanLII)”
https://www.canlii.org/en/ab/abca/doc/1996/1996abca23/1996abca23.html (accessed 19 July 2026) at para 18.
¹¹ “R. v. Andrews, 1996 ABCA 23 (CanLII)”
https://www.canlii.org/en/ab/abca/doc/1996/1996abca23/1996abca23.html (accessed 19 July 2026) at para 19.
¹² Cf, “R. v. Thompson, 2012 ONCJ 377 (CanLII)”
https://www.canlii.org/en/on/oncj/doc/2012/2012oncj377/2012oncj377.html (accessed 19 July 2026) at para 13.
¹³ Cf, “R. v. Castelblanco Velasco, 2019 ONCJ 84 (CanLII)”
https://www.canlii.org/en/on/oncj/doc/2019/2019oncj84/2019oncj84.html (accessed 17 July 2026) at para 117.
¹⁴ Cf, “R. v. Castelblanco Velasco, 2019 ONCJ 84 (CanLII)”
https://www.canlii.org/en/on/oncj/doc/2019/2019oncj84/2019oncj84.html (accessed 17 July 2026) at para 118.
7. Does an accused’s having a concentration of drugs and/or alcohol in the accused’s body at which it is unlawful for the accused to operate a conveyance prove that the accused is impaired in ability to operate a conveyance by alcohol and/or a drug?
Because an accused can be convicted of operating a conveyance with a concentration of drugs and/or alcohol in the accused’s body at which it is unlawful for the accused to operate a conveyance but can be acquitted at the same trial of operation while impaired by a drug and/or alcohol, the mere fact that an accused has a concentration of drugs and/or alcohol,¹⁵ in the accused’s body at which it is unlawful for the accused to operate a conveyance does not prove that the accused is impaired in ability to operate a conveyance by alcohol and/or a drug.
¹⁵ See, e.g., “R. v. Deshpande, 2021 ONCJ 699 (CanLII)”
https://www.canlii.org/en/on/oncj/doc/2021/2021oncj699/2021oncj699.html (accessed 18 July 2026) at paras 1, 82-85, 100.
8. What is acceptable proof that an accused is impaired in the ability to operate a conveyance by alcohol and/or a drug?
There is no special test for determining impairment of the ability to operate a conveyance by alcohol and/or a drug.¹⁶
Courts have considered a number of factors in determining whether an accused’s ability to operate a conveyance was impaired as a result of alcohol and/or a drug, including lay opinions from witnesses, accidents, speech, appearance of eyes and face, gross and fine motor skills, mental ability and emotional state, odour of alcohol, alternative explanations for indicia of impairment, and admissions of consumption of drugs and/or alcohol by the accused.¹⁷
In any proceedings for impaired operation, evidence that the accused, without reasonable excuse, failed or refused to comply with a demand to provide a sample or to submit to testing for the purpose of providing evidence that the accused’s operation of a conveyance was unlawful due to intoxicants is admissible, and the Court may draw an inference adverse to the accused from that evidence.¹⁸ Whether the Court draws this inference should depend upon the circumstances because there may be times when the refusal occurs for reasons which, although not legally valid, fall short of satisfying the Court that the refusal arose from consciousness of guilt.¹⁹
¹⁶ Cf, “R. v. Ramroop, 2021 ONCA 642 (CanLII)”
https://www.canlii.org/en/on/onca/doc/2021/2021onca642/2021onca642.html (accessed 19 July 2026) at para 11.
¹⁷ Cf, “R. v. Castelblanco Velasco, 2019 ONCJ 84 (CanLII)”
https://www.canlii.org/en/on/oncj/doc/2019/2019oncj84/2019oncj84.html (accessed 17 July 2026) at para 122.
¹⁸ “Criminal Code, RSC 1985, c C-46” (26 May 2026)
https://www.canlii.org/en/ca/laws/stat/rsc-1985-c-c-46/latest/rsc-1985-c-c-46.html (accessed 17 July 2026) at ss 320.14(1)(a), 320.27(1), 320.27(1)(a), 320.27(1)(b), 320.27(1)(c), 320.27(2), 320.28(1), 320.28(1)(a), 320.28(1)(a)(i), 320.28(1)(a)(ii), 320.28(1)(b), 320.28(2), 320.28(2)(a), 320.28(2)(b), 320.28(3), 320.28(4), 320.28(4)(a), 320.28(4)(b), 320.31(10).
¹⁹ “R v McGinnes, 2020 ABPC 269 (CanLII)”
https://www.canlii.org/en/ab/abpc/doc/2020/2020abpc269/2020abpc269.html (accessed 17 July 2026) at paras 127-129.
9. How should claims that an accused involuntarily consumed an intoxicant be dealt with?
An accused is presumed to have become intoxicated voluntarily.²⁰ Involuntary intoxication occurs when a person either unknowingly takes intoxicants (as occurs when an accused consumes a spiked drink) or knowingly takes drugs whose effects are unknown to the accused.²¹
The defence of involuntary intoxication, although often conflated and/or confused with the defence of automatism, is separate from the defence of automatism.²²
Any degree of intoxication, even if not intoxication causing automatism, can support a defence of involuntary intoxication.²³
Because intoxication’s voluntariness is assumed, absent evidence to the contrary, the accused must raise a reasonable doubt about voluntary consumption before a defence of involuntary intoxication can succeed.²⁴ Although the presumption of voluntary intoxication is rebuttable, the defence only needs to point to evidence that raises a reasonable doubt about the intoxication’s voluntariness and does not need to prove anything on a balance of probabilities.²⁵ This means that when the accused raises the defence of involuntary intoxication, the accused has no burden to prove anything, and the burden remains with the Crown to prove beyond a reasonable doubt that the accused’s act was voluntary.²⁶
When an accused raises the defence of involuntary intoxication to the charge of impaired operation, the accused is, for the defence’s purpose, conceding that the accused’s actions fulfilled the actus reus of the charge of impaired operation but is alleging that the accused lacked the mens rea sufficient to be convicted of impaired operation.²⁷
If the accused can raise a reasonable doubt about the intoxication’s voluntariness and whether the accused realized impairment before operating a conveyance, then the accused must be acquitted of offences related to operating a conveyance unlawfully due to intoxicants.²⁸
An accused’s recklessness about a substance’s impairing effects on the ability to operate a conveyance is sufficient to establish mens rea for impaired operation.²⁹ But when an accused is genuinely involuntarily impaired, that very impairment may serve as a legitimate explanation for why the accused, having become impaired, failed to avoid unlawfully operating a conveyance.³⁰
²⁰ See, e.g., “R. v. McGrath, 2013 ONCJ 528 (CanLII)”
https://www.canlii.org/en/on/oncj/doc/2013/2013oncj528/2013oncj528.html (accessed 17 July 2026) at paras 1, 33, 35.
²¹ “R. v. McGrath, 2013 ONCJ 528 (CanLII)”
https://www.canlii.org/en/on/oncj/doc/2013/2013oncj528/2013oncj528.html (accessed 17 July 2026) at para 6
²² “R. v. Hallahan, 2021 ONCJ 156 (CanLII)”
https://www.canlii.org/en/on/oncj/doc/2021/2021oncj156/2021oncj156.html (accessed 17 July 2026) at paras 4, 24-28.
²³ “R. v. McGrath, 2013 ONCJ 528 (CanLII)”
https://www.canlii.org/en/on/oncj/doc/2013/2013oncj528/2013oncj528.html (accessed 17 July 2026) at para 8.
²⁴ “R. v. McGrath, 2013 ONCJ 528 (CanLII)”
https://www.canlii.org/en/on/oncj/doc/2013/2013oncj528/2013oncj528.html (accessed 17 July 2026) at para 12.
²⁵ “R. v. Magdallah, 2024 ONSC 3660 (CanLII)”
https://www.canlii.org/en/on/onsc/doc/2024/2024onsc3660/2024onsc3660.html (accessed 17 July 2026) at paras 1, 11.
²⁶ “R. v. Hallahan, 2021 ONCJ 156 (CanLII)”
https://www.canlii.org/en/on/oncj/doc/2021/2021oncj156/2021oncj156.html (accessed 17 July 2026) at para 23.
²⁷ “R. v. White, 2022 ONCJ 600 (CanLII)”
https://www.canlii.org/en/on/oncj/doc/2022/2022oncj600/2022oncj600.html (accessed 17 July 2026) at paras 1-2, 5, 27.
²⁸ “R. v. McGrath, 2013 ONCJ 528 (CanLII)”
https://www.canlii.org/en/on/oncj/doc/2013/2013oncj528/2013oncj528.html (accessed 17 July 2026) at para 13.
²⁹ “R. v. White, 2022 ONCJ 600 (CanLII)”
https://www.canlii.org/en/on/oncj/doc/2022/2022oncj600/2022oncj600.html (accessed 17 July 2026) at para 37.
³⁰ “R. v. Domb, 2011 ONCJ 756 (CanLII)”
https://www.canlii.org/en/on/oncj/doc/2011/2011oncj756/2011oncj756.html (accessed 17 July 2026) at paras 1-6, 86, 88.
10. What is "Operation While Impaired" as Driving?
Operation while impaired as driving must be distinguished from merely defective driving, even criminally bad driving.
When the trier of fact is left with a reasonable doubt about whether the accused was impaired by alcohol and/or a drug when the accused engaged in defective driving and/or is left with a reasonable doubt about whether the accused’s defective driving was caused by the accused’s being impaired by alcohol and/or a drug, then even when the trier of fact concludes that the accused consumed alcohol and/or a drug before the accused was driving, had a concentration of a drug and/or alcohol within the accused’s body sufficient to convict the accused of unlawfully operating a conveyance, and was obviously intoxicated by a drug and/or alcohol after the defective driving, the accused must be acquitted of impaired operation as driving.³¹
When there is no acceptable evidence that the accused had an illegally high BAC, then the fact that the accused’s breath smelled of alcohol, the accused had bloodshot eyes, and the accused, despite being fairly steady upon his feet, tripped on treacherous terrain cannot combine with the fact that the accused collided with a road’s meridian to convict the accused of impaired operation because a reasonable doubt remains about whether the accused’s bad driving was related to the accused’s recklessness rather than the accused’s being impaired.³²
It is possible for an accused, despite indisputably having been impaired while driving, to be acquitted of impaired driving by citing evidence that the accused’s poor driving was caused not by impairment but by defects in the vehicle being driven.³³ Similar arguments can be raised successfully by citing the strange and unsafe route taken by the road, which even a non-intoxicated driver would find dangerous to drive through³⁴ and due to the weather conditions when the accused was driving and the surface over which the accused had to drive,³⁵ although they are made stronger when there is no unambiguous evidence that the accused was intoxicated.³⁶
It is possible for a driver to be witnessed driving a vehicle into a ditch, to smell of alcohol, to admit to having consumed alcohol, and to be convicted of refusing to provide a breath sample relating to the accident but be acquitted of impaired operation because there were no consistent accounts that the accused was physically impaired by intoxication and the accused’s explanation for the accident preserves a reasonable doubt.³⁷
³¹ Cf, e.g., “R. v. Deshpande, 2021 ONCJ 699 (CanLII)”
https://www.canlii.org/en/on/oncj/doc/2021/2021oncj699/2021oncj699.html (accessed 18 July 2026) at paras 1, 82-85, 100.
³² “R. v. Vassie, 2001 CanLII 947 (SK PC)”
https://www.canlii.org/en/sk/skpc/doc/2001/2001canlii947/2001canlii947.html (accessed 17 July 2026) at paras 1-2, 4, 18-19, 25-26.
³³ “R. v. Bacci, 2018 ONCA 928 (CanLII)”
https://www.canlii.org/en/on/onca/doc/2018/2018onca928/2018onca928.html (accessed 17 July 2026) at paras 21, 31, 33, 48.
³⁴ “R. v. Hammett, 2018 ONCJ 778 (CanLII)”
https://www.canlii.org/en/on/oncj/doc/2018/2018oncj778/2018oncj778.html (accessed 17 July 2026) at paras 217-224.
³⁵ “R. v. Bekkers, 2012 BCSC 471 (CanLII)”
https://www.canlii.org/en/bc/bcsc/doc/2012/2012bcsc471/2012bcsc471.html (accessed 17 July 2026) at paras 1, 361-363.
³⁶ “R. v. Bekkers, 2012 BCSC 471 (CanLII)”
https://www.canlii.org/en/bc/bcsc/doc/2012/2012bcsc471/2012bcsc471.html (accessed 17 July 2026) at paras 505-507, “R. v. Hammett, 2018 ONCJ 778 (CanLII)”
https://www.canlii.org/en/on/oncj/doc/2018/2018oncj778/2018oncj778.html (accessed 17 July 2026) at paras 217, 221.
³⁷“R. v. Wright, 2008 ONCJ 65 (CanLII)”
https://www.canlii.org/en/on/oncj/doc/2008/2008oncj65/2008oncj65.html (accessed 17 July 2026) at paras 1-13.
11. What is "Operation While Impaired" as Care or Control?
An accused who raises at least a reasonable doubt about whether the accused was intoxicated at the relevant time cannot be convicted of "Operation While Impaired" as care or control.³⁸
In proceedings for impaired operation, if it is proven that the accused occupied the seat or position ordinarily occupied by a person who operates a conveyance, the accused is presumed to have been operating the conveyance unless the accused establishes that the accused did not occupy that seat or position for the purpose of setting the conveyance in motion.³⁹ This presumption cannot be rebutted merely by establishing that the conveyance was inoperable and posed no risk to the general public.⁴⁰ The standard of proof in rebutting the presumption is a balance of probabilities.⁴¹ Proof on a balance of probabilities means that the trier of fact must scrutinize the relevant evidence with care in order to determine whether it is more likely than not that an alleged event occurred.⁴²
Even when this presumption is rebutted, the accused can be convicted of impaired operation as care or control when the Crown is able to prove beyond a reasonable doubt that the accused, while impaired at the relevant time, was in care or control of the conveyance.⁴³
Even when the accused is found impaired in a stationary vehicle’s driver’s seat, care and control are only established when there is a risk that the vehicle will unintentionally be set in motion; a risk that through negligence a stationary or inoperable vehicle may endanger the individual or others; or a risk that the accused, having decided not to drive, will change the mind and drive while still impaired.⁴⁴ Accordingly, when the accused, having rebutted the presumption of care and control arising from being found in the driver’s seat, proves to the Court that no intention to drive was present in the accused’s mind when the accused was impaired in the vehicle, the evidence reveals that the accused would have had to engage in a series of actions in order to cause the vehicle to move even if the accused had had a change of mind, and there is no evidence that the accused was being negligent in the stationary or inoperable vehicle in such way that the vehicle could harm other people, then the accused has established a lack of de facto care and control and must be acquitted.⁴⁵
³⁸ See, e.g., albeit under the old statutory scheme, “R. v. Bullock, 2018 ONCJ 250 (CanLII)”
https://www.canlii.org/en/on/oncj/doc/2018/2018oncj250/2018oncj250.html (accessed 17 July 2026) at paras 1, 13-16.
³⁹ “Criminal Code, RSC 1985, c C-46” (26 May 2026)
https://www.canlii.org/en/ca/laws/stat/rsc-1985-c-c-46/latest/rsc-1985-c-c-46.html (accessed 17 July 2026) at ss 320.14(1)(a), 320.35.
⁴⁰ “R. v. Maniatis, 2024 CanLII 24885 (ON SC)”
https://www.canlii.org/en/on/onsc/doc/2024/2024canlii24885/2024canlii24885.html (accessed 17 July 2026) at paras 1, 6, 16-18, 44, 47-48.
⁴¹ See, e.g., “R. v. Aggarwal, 2022 ONSC 6213 (CanLII)”
https://www.canlii.org/en/on/onsc/doc/2022/2022onsc6213/2022onsc6213.html (accessed 17 July 2026) at para 11.
⁴² “F.H. v. McDougall, 2008 SCC 53 (CanLII), [2008] 3 SCR 41”
https://www.canlii.org/en/ca/scc/doc/2008/2008scc53/2008scc53.html (accessed 17 July 2026) at para 49.
⁴³ See, e.g., “R. v. Osbourne, 2021 ONCJ 58 (CanLII)”
https://www.canlii.org/en/on/oncj/doc/2021/2021oncj58/2021oncj58.html (accessed 17 July 2026) at paras 1-2, 19-20, 27-28.
⁴⁴ “R. v. Smits, 2012 ONCA 524 (CanLII)”
https://www.canlii.org/en/on/onca/doc/2012/2012onca524/2012onca524.html (accessed 17 July 2026) at paras 52-53.
⁴⁵ “R. v O’Brien, 2020 CanLII 55107 (NL PC)”
https://www.canlii.org/en/nl/nlpc/doc/2020/2020canlii55107/2020canlii55107.html (accessed 17 July 2026) at paras 1, 11-13.