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Crown Court

Manslaughter by reason of diminished responsibility

Common law, Homicide Act 1957, s.2

Effective from 01 November 2018

Triable only on indictment
Maximum: Life imprisonment
Offence range: 3 – 40 years’ custody

This is a Schedule 19 offence for the purposes of sections 274 and 285 (required life sentence for offence carrying life sentence) of the Sentencing Code.

For offences committed on or after 3 December 2012, this is an offence listed in Part 1 of Schedule 15 for the purposes of sections 273 and 283 (life sentence for second listed offence) of the Sentencing Code. This is a specified offence for the purposes of sections 266 and 279 (extended sentence for certain violent, sexual or terrorism offences) of the Sentencing Code.

The type of manslaughter (and thereby the appropriate guideline) should have been identified prior to sentence. If there is any dispute or uncertainty about the type of manslaughter that applies the judge should give clear reasons for the basis of sentence.

User guide for this offence


Guideline users should be aware that the Equal Treatment Bench Book covers important aspects of fair treatment and disparity of outcomes for different groups in the criminal justice system. It provides guidance which sentencers are encouraged to take into account wherever applicable, to ensure that there is fairness for all involved in court proceedings.

Step 1 – Assessing the degree of responsibility retained: high, medium or lower

  • A conviction for manslaughter by reason of diminished responsibility necessarily means that the offender’s ability to understand the nature of the conduct, form a rational judgment and/or exercise self-control was substantially impaired.
  • The court should determine what level of responsibility the offender retained:
    • High;
    • Medium; or
    • Lower
  • The court should consider the extent to which the offender’s responsibility was diminished by the mental disorder at the time of the offence with reference to the medical evidence and all the relevant information available to the court.
  • The degree to which the offender’s actions or omissions contributed to the seriousness of the mental disorder at the time of the offence may be a relevant consideration. For example:
    • where an offender exacerbates the mental disorder by voluntarily abusing drugs or alcohol or by voluntarily failing to seek or follow medical advice this may increase responsibility. In considering the extent to which the offender’s behaviour was voluntary, the extent to which a mental disorder has an impact on the offender’s ability to exercise self-control or to engage with medical services will be relevant.
  • The degree to which the mental disorder was undiagnosed and/or untreated may be a relevant consideration. For example:
    • where an offender has sought help but not received appropriate treatment this may reduce responsibility.

Harm

For all cases of manslaughter the harm caused will inevitably be of the utmost seriousness. The loss of life is taken into account in the sentencing levels at step two.

Step 2 – Starting point and category range

Having determined the category at step one, the court should use the corresponding starting point to reach a sentence within the category range in the table below. The starting point applies to all offenders irrespective of plea or previous convictions.

An adjustment from the starting point, upwards or downwards, may be necessary to reflect particular features of the case (for example where a case falls close to a borderline between categories).

Level of responsibility retained
High Medium Lower
Starting point
24 years’ custody
Starting point
15 years’ custody
Starting point
7 year’s custody
Category range
15 – 40 years’ custody
Category range
10 – 25 years’ custody
Category range
3 – 12 years’ custody

Note: The table is for a single offence of manslaughter resulting in a single fatality. Where another offence or offences arise out of the same incident or facts concurrent sentences reflecting the overall criminality of offending will ordinarily be appropriate: please refer to the Totality guideline and step eight of this guideline.

The tables below contain a non-exhaustive list of additional factual elements providing the context of the offence and factors relating to the offender. Identify whether any combination of these, or other relevant factors, should result in a further upward or downward adjustment. In some cases, having considered these factors, it may be appropriate to move outside the identified category range.

Care should be taken to avoid double counting factors already taken into account in assessing the level of responsibility retained

Factors increasing seriousness

Statutory aggravating factors:

  • having regard to a) the nature of the offence to which the conviction relates and its relevance to the current offence; and b) the time that has elapsed since the conviction (See step three for a consideration of dangerousness)

Other aggravating factors:

  • History of violence or abuse towards victim by offender (which may include coercive or controlling behaviour)
  • Use of strangulation, suffocation or asphyxiation
  • Involvement of other(s) through coercion, intimidation or exploitation
  • Significant mental or physical suffering caused to the deceased
  • Concealment, destruction, defilement or dismemberment of the body

Factors reducing seriousness or reflecting personal mitigation

  • Intention to cause serious bodily harm rather than to kill
  • History of significant violence or abuse towards the offender by the victim (which may include coercive or controlling behaviour)
  • The offender acted in self-defence or in fear of violence (where not amounting to a defence)
  • The offender made genuine and sustained attempts to seek help for the mental disorder
  • Belief by the offender that the killing was an act of mercy

Step 3 – Consideration of dangerousness

  • When sentencing to a life sentence the notional determinate term (identified at step two above) should be used as the basis for setting the minimum term.

Step 4 – Consideration of mental health disposals (Mental Health Act 1983)

Where:

(i) the evidence of medical practitioners suggests that the offender is currently suffering from a mental disorder,

(ii) treatment is available, and

(iii) the court considers that a hospital order (with or without a restriction) may be an appropriate way of dealing with the case, the court should consider all sentencing options including a section 45A direction and consider the importance of a penal element in the sentence taking into account the level of responsibility assessed at step one.

Section 45A hospital and limitation direction

a. Before a hospital order is made under section 37 (with or without a restriction order under section 41), consider whether the mental disorder can appropriately be dealt with by custody with a hospital and limitation direction under section 45A. In deciding whether a section 45A direction is appropriate the court should bear in mind that the limitation direction will cease to have effect at the automatic release date of a determinate sentence.

b. If a penal element is appropriate and the mental disorder can appropriately be dealt with by a direction under section 45A, then the judge should make such a direction. (Not available for a person under the age of 21 at the time of conviction).

Section 37 hospital order and section 41 restriction order

c. If a section 45A direction is not appropriate the court must then consider (assuming the conditions in section 37(2)(a) are satisfied) whether the matters referred to in section 37(2)(b) would make a hospital order (with or without a restriction order under section 41) the most suitable disposal. The court should explain why a penal element is not appropriate.

Step 5 – IN ALL CASES consider factors that may warrant an adjustment to the sentence

Cases of manslaughter by reason of diminished responsibility vary considerably on the facts of the offence and on the circumstances of the offender.

  • The court should review whether the sentence as a whole meets the objectives of punishment, rehabilitation and protection of the public in a fair and proportionate way.
  • Relevant factors will include the psychiatric evidence and the regime on release.
  • An adjustment may require a departure from the sentence range identified at step two above.

Step 6 – Consider any factors which indicate a reduction for assistance to the prosecution

The court should take into account section 74 of the Sentencing Code (reduction in sentence for assistance to prosecution) and any other rule of law by virtue of which an offender may receive a discounted sentence in consequence of assistance given (or offered) to the prosecutor or investigator.

Step 7 – Reduction for guilty pleas

The court should take account of any potential reduction for a guilty plea in accordance with section 73 of the Sentencing Code and the Reduction in Sentence for a Guilty Plea guideline. Note: the limitations on reductions for murder do not apply to manslaughter.

Step 8 – Totality principle

If sentencing an offender for more than one offence, or where the offender is already serving a sentence, consider whether the total sentence is just and proportionate to the overall offending behaviour in accordance with the Totality guideline.

Step 9 – Compensation and ancillary orders

In all cases the court should consider whether to make compensation and/or other ancillary orders.

Step 10 – Reasons

Section 52 of the Sentencing Code imposes a duty to give reasons for, and explain the effect of, the sentence.

Step 11 – Consideration for time spent on bail (tagged curfew)

The court must consider whether to give credit for time spent on bail in accordance with section 240A of the Criminal Justice Act 2003 and section 325 of the Sentencing Code.

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