R v William Cosier

R v William Cosier

There was no sufficient evidence of loss of control to justify leaving the partial defence to the jury, as the appellant's actions were rational and deliberate before and after the stabbing, and there was no assertion or evidence of loss of control. The minimum term of 25 years was manifestly excessive given the mitigating factors, and should be reduced to 21 years and 134 days.

Parties
Respondent: R; Appellant: William Cosier
Jurisdiction
England and Wales
Judgment Date
28 January 2026
Procedural Posture
Criminal Appeal / Appeal Against Conviction and Sentence
Outcome
Appeal against conviction dismissed; appeal against sentence allowed in part
Legal Topics
Murder, Partial Defence, Loss of Control, Self Defence, Sentencing, Aggravating and Mitigating Factors
Criminal Law Murder Partial Defence Loss of Control Self Defence Sentencing Aggravating and Mitigating Factors

Case Brief

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Parties

R

Respondent

William Cosier

Appellant

Procedural Posture

Criminal Appeal / Appeal Against Conviction and Sentence

Legal Issues

  1. 1 Whether the trial judge erred in refusing to leave the partial defence of loss of control to the jury
  2. 2 Whether the sentence imposed was manifestly excessive

Ratio Decidendi

There was no sufficient evidence of loss of control to justify leaving the partial defence to the jury, as the appellant's actions were rational and deliberate before and after the stabbing, and there was no assertion or evidence of loss of control. The minimum term of 25 years was manifestly excessive given the mitigating factors, and should be reduced to 21 years and 134 days.

Court Disposition

Appeal against conviction dismissed; appeal against sentence allowed in part

Orders

  • Conviction appeal dismissed
  • Minimum term of imprisonment reduced from 25 years to 21 years and 134 days