Tunstill, R. v

For infanticide under section 1(1) of the Infanticide Act 1938, a mother’s failure to recover fully from childbirth need not be the sole cause of a disturbed balance of mind. It is sufficient that the effects of birth are an operative or substantial cause, even if a pre-existing mental disorder also contributes and the respective effects cannot be disentangled.

The required causal inquiry concerns the disturbance of mind, not a further causal link between that disturbance and the fatal act. Where there is evidence capable of satisfying that test, causation is for the jury and infanticide must be left as an alternative verdict.

The appellant was convicted at the Crown Court at Preston of murdering her newborn daughter and was sentenced to life imprisonment with a minimum term of 20 years. Her case at trial included diminished responsibility. She also sought to have infanticide left to the jury as an alternative verdict.

The trial judge declined to leave infanticide. He considered that the medical evidence attributed any disturbed balance of mind partly to a pre-existing mental disorder, rather than solely to a failure to recover from childbirth. The appeal challenged that ruling and the safety of the murder conviction.

1. Appeal allowed. The murder conviction was unsafe because the judge should have left infanticide to the jury as an alternative verdict. The verdict was quashed and a retrial ordered.

2. Section 1(1) of the Infanticide Act 1938 asks whether the balance of the mother’s mind was disturbed by reason of a failure fully to recover from childbirth. The phrase does not mean solely by reason of childbirth. The effects of birth need only be an operative or substantial cause of the disturbance, even if an underlying mental disorder is another cause.

3. The court declined to apply the obiter observation in R v Kai-Whitewind [2005] 2 Cr App R 31 that no circumstances other than childbirth or lactation were relevant. A restrictive reading would treat a mother with a pre-existing but fragile mental state less favourably than a mother affected only by childbirth. That would be unnecessarily harsh and inconsistent with the merciful purpose of the legislation.

4. The relevant causal link is between childbirth and the disturbed balance of mind. The Act does not require a further causal link between that disturbance and the act causing death. The general criminal-law approach to concurrent causes, illustrated by R v Smith [1959] 2 QB 35 and R v Hughes [2014] 1 Cr App R 6, supported that construction.

5. The psychiatric evidence was capable of showing that childbirth caused or substantially contributed to a disturbed balance of mind. The competing Crown evidence did not permit the judge to withdraw the issue. Causation was for the jury after proper direction.

• Court of Appeal (Criminal Division). In [2018] EWCA Crim 1696, the court allowed the appeal, quashed the murder conviction and ordered a retrial.
• Crown Court at Preston. On 19 June 2017, the appellant was convicted of murder and sentenced to life imprisonment with a minimum term of 20 years, less time on remand.