Canada Judgment

Supreme Court of Canada

R. v. Strathdee

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Source document

01

Holding and result

The Court affirmed conviction because the stabbing was within the scope of the group attack and the appellant's participation in the group assault was a significant contributing cause of the victim's death, so co‑principal liability applied notwithstanding that only one assailant inflicted the fatal wound; the trial judge erred by isolating which individual caused the wound rather than assessing contribution to the death.

Court disposition

Appeal dismissed; conviction for unlawful act manslaughter affirmed.

Orders

  • Appeal dismissed.
  • Conviction for unlawful act manslaughter entered by the Alberta Court of Appeal is affirmed.

02

Material facts

Parties

Tyler Gordon Strathdee

Appellant Counsel: Graham Johnson; Tania Shapka

Her Majesty The Queen

Respondent Counsel: Julie Morgan

Amounts and remedies

  • Case Number: 39,556
  • Decision Year: 2,021

03

Procedural history

  1. Posture

    Criminal Appeal / Appeal to the Supreme Court of Canada; Judgment on Appeal From the Alberta Court of Appeal

04

Questions and positions

Legal issues

Party arguments

Applicant
The appellant argued the acquittal was proper because the Crown failed to prove beyond a reasonable doubt that he inflicted the fatal stab wound and the evidence showed only a single perpetrator applied the fatal force.
Respondent
The Crown argued the appellant was properly convicted as a co‑principal because he participated in the group assault and, absent a discrete intervening act, the actions of all assailants can be a significant contributing cause of death even if a single assailant inflicted the fatal wound.

05

Court’s reasoning

  1. 01

    R. v. Strathdee, 2021 SCC 40; Criminal Code ss.21(1)(a),(c)

    Joint/co‑principal liability arises when two or more individuals come together with an intention to commit an offence, are present during its commission, and contribute to its commission.

  2. 02

    R. v. Strathdee, 2021 SCC 40

    In manslaughter, triers of fact should focus on whether an accused's actions were a significant contributing cause of death rather than on which perpetrator inflicted which wound.

  3. 03

    R. v. Strathdee, 2021 SCC 40; discussion consistent with R. v. Pickton, 2010 SCC 32

    Absent a discrete or intervening event, the actions of all assailants in a group assault can constitute a significant contributing cause to all injuries sustained, including fatal injuries caused by one participant.

06

Ratio, limits and disposition

Ratio decidendi

The Court affirmed conviction because the stabbing was within the scope of the group attack and the appellant's participation in the group assault was a significant contributing cause of the victim's death, so co‑principal liability applied notwithstanding that only one assailant inflicted the fatal wound; the trial judge erred by isolating which individual caused the wound rather than assessing contribution to the death.

Obiter and limits

  • Clarification that any implication from R. v. Cabrera that joint/co‑principal liability is automatically negated when only a single perpetrator applied force is incorrect.
  • Proper reading of R. v. Pickton is consistent with the principle that contribution to the fatal result is the focus in party liability for manslaughter.

Court disposition

Appeal dismissed; conviction for unlawful act manslaughter affirmed.

  • Appeal dismissed.
  • Conviction for unlawful act manslaughter entered by the Alberta Court of Appeal is affirmed.

Source and reliance status

Supreme Court of Canada · 15 October 2021

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Judgment reading view

Judgment text

The complete available source text.

Source document

Supreme Court of Canada

Judgment· 15 October 2021

2021 SCC 40

R. v. Strathdee Collection Supreme Court Judgments Date 2021-10-15 Neutral citation 2021 SCC 40 Report [2021] 3 SCR 52 Case number 39556 Judges Wagner, Richard; Moldaver, Michael J.; Karakatsanis, Andromache; Côté, Suzanne; Brown, Russell; Rowe, Malcolm; Martin, Sheilah; Kasirer, Nicholas; Jamal, Mahmud On appeal from Alberta Notes SCC Case Information Decision Content

SUPREME COURT OF CANADA Citation: R. v. Strathdee, 2021 SCC 40, [2021] 3 S.C.R. 52 Appeal Heard: October 15, 2021 Judgment Rendered: October 15, 2021 Docket: 39556 Between: Tyler Gordon Strathdee Appellant and Her Majesty The Queen Respondent Coram: Wagner C.J. and Moldaver, Karakatsanis, Côté, Brown, Rowe, Martin, Kasirer and Jamal JJ. Unanimous Judgment Read By: (paras. 1 to 5) Rowe J. Tyler Gordon Strathdee Appellant v. Her Majesty The Queen Respondent Indexed as: R. v. Strathdee 2021 SCC 40 File No.: 39556. 2021: October 15. Present: Wagner C.J. and Moldaver, Karakatsanis, Côté, Brown, Rowe, Martin, Kasirer and Jamal JJ. on appeal from the court of appeal for alberta Criminal law — Parties to offence — Co‑principal liability — Group assault — Accused part of group that entered apartment and assaulted several occupants — One occupant dying of single stab wound — Accused charged with manslaughter — Trial judge acquitting accused on basis that single stab wound could only have been caused by one principal offender and that Crown had not proven beyond reasonable doubt that accused inflicted stab wound — Court of Appeal holding that trial judge erred in law in failing to properly assess accused’s culpability as co‑principal to manslaughter in light of her finding that accused participated in group assault — Court of Appeal setting aside acquittal and entering conviction — Conviction upheld. Cases Cited Referred to: R. v. Cabrera, 2019 ABCA 184, 95 Alta. L.R. (6th) 258, aff’d R. v. Shlah, 2019 SCC 56, [2019] 4 S.C.R. 136; R. v. Pickton, 2010 SCC 32, [2010] 2 S.C.R.

198. Statutes and Regulations Cited Criminal Code, R.S.C. 1985, c. C‑46, ss. 21(1)(a), (c), 691(2)(b). APPEAL from a judgment of the Alberta Court of Appeal (Fraser C.J. and Watson and Pentelechuk JJ.A.), 2020 ABCA 443, 21 Alta. L.R. (7th) 72, 410 C.C.C. (3d) 46, 463 D.L.R. (4th) 193, [2021] 5 W.W.R. 456, [2020] A.J. No. 1357 (QL), 2020 CarswellAlta 2352 (WL Can.), setting aside the acquittal of the accused for manslaughter entered by Goss J., 2019 ABQB 479, [2019] A.J. No. 853 (QL), 2019 CarswellAlta 1310 (WL Can.), and entering a conviction. Appeal dismissed. Graham Johnson and Tania Shapka, for the appellant. Julie Morgan, for the respondent. The judgment of the Court was delivered orally by [1] Rowe J. — Mr. Strathdee appeals as of right to this Court under s. 691(2)(b) of the Criminal Code, R.S.C. 1985, c. C‑46, on the basis that the Alberta Court of Appeal overturned his acquittal for unlawful act manslaughter and entered a conviction (2020 ABCA 443, 21 Alta. L.R. (7th) 72). The trial judge, sitting as judge alone, had acquitted Mr. Strathdee after considering joint/co‑principal liability and abetting under s. 21(1)(a) and 21(1)(c), respectively, of the Criminal Code (2019 ABQB 479). The charges against Mr. Strathdee stemmed from a group assault in which several victims sustained multiple injuries and one victim, Mr. Tong, sustained a single stab wound which caused his

death. [2] We agree with the Court of Appeal that there is no basis for the view that the stabbing of Mr. Tong was a distinct act outside the scope of the group attack. [3] Having regard to the findings of fact in paras. 137 and 156‑59 (CanLII) of the trial decision, and the statement of law set out by the Court of Appeal at paras. 61, 66 and 68 of its decision, this Court affirms the result of the Alberta Court of Appeal that Mr. Strathdee is guilty of unlawful act manslaughter. [4] We also wish briefly to clarify a statement of law in R. v. Cabrera, 2019 ABCA 184, 95 Alta. L.R. (6th) 258, aff’d R. v. Shlah, 2019 SCC 56, [2019] 4 S.C.R.

136. Any implication from Cabrera that joint/co‑principal liability is automatically eliminated if the evidence demonstrates application of force by only a single perpetrator is not accurate. Joint/co‑principal liability flows whenever two or more individuals come together with an intention to commit an offence, are present during the commission of the offence, and contribute to its commission. In the context of manslaughter, triers of fact should focus on whether an accused’s actions were a significant contributing cause of death, rather than focusing on which perpetrator inflicted which wound or whether all of the wounds were caused by a single individual. In the context of group assaults, absent a discrete or intervening event, the actions of all assailants can constitute a significant contributing cause to all injuries sustained. Properly read, the discussion of party liability in R. v. Pickton, 2010 SCC 32, [2010] 2 S.C.R. 198, is fully consistent with the foregoing. [5] Accordingly, we would dismiss the appeal. Judgment accordingly. Solicitors for the appellant: Dawson Duckett Garcia & Johnson, Edmonton. Solicitor for the respondent: Attorney General of Alberta, Calgary.

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Authorities

Authorities used by the court

Cases, legislation, regulations, and constitutional provisions identified in the available record.

R. v. Cabrera, 2019 ABCA 184

Case cited

R. v. Shlah, 2019 SCC 56

Case cited

R. v. Pickton, 2010 SCC 32

Case cited

R. v. Strathdee, 2021 SCC 40

Case cited

Criminal Code, R.S.C. 1985, c. C-46, ss. 21(1)(a), 21(1)(c), 691(2)(b)

Legislation

Legislation referenced in the available case record.

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