If there seems to be no possibility of the prosecution discontinuing the case, then the material gathered for the purposes of making the relevant representations to the CPS can be used, in the event of a guilty plea or conviction, for the purposes of mitigation.

There is a strong, but encouraging, distinction between the regular experience of practitioners who are presenting details of their client's HIV status as a point of mitigation and the few Court of Appeal authorities on the relevance of a defendant's HIV diagnosis.

The general experience is that sentencing judges and magistrates are prepared to give considerable weight to the consequences of an HIV or AIDS diagnosis for either the defendant or their partner in terms of the likely impact on their life expectancy and quality of life and, as a result, to reduce substantially the 'usual' penalty. It must be mentioned at this point that although the HIV status of a defendant's partner can be relevant for the purposes of mitigation it does not appear to be a point which the CPS are obliged or ready to take into account in considering whether to drop a case.

There are a number of Court of Appeal authorities (three of them, confusingly, involving appellants named Moore) which specifically consider the relevance of an HIV diagnosis as a point of mitigation.

R v Moore (Archibald) ((1990) 12 Cr. App R. (S) 384), where the appellant had been convicted of two substantial burglaries and asked for three other offences to be taken into consideration. The appellant had been diagnosed in 1986 as HIV–positive and the lower court apparently found that there was a likelihood that he would develop AIDS within about two years. The Court of Appeal accepted that his treatment would be more difficult in prison, but Lord Lane C. J. ruled as follows:

We ... are asked in this case to mitigate the penalty of five years imprisonment imposed upon the appellant because this man is HIV–positive and it is suggested, but not based upon any medical evidence apart from second hand evidence via the defendant himself, that his life expectancy may thereby be diminished. As I say, we have no medical evidence as to the length of life expectancy.

Nevertheless, assuming that such evidence does exist, we do not consider that it is the function of this court to base its decision upon possible medical considerations of this sort. ... We do not know what the future may hold with regard to medical science and medical expertise. We do not know what the future may hold with regard to this particular appellant. If the time should come when it is no longer possible, for practical reasons, or for reasons of humanity, to hold this appellant in prison because of his physical condition, then that is the job of the Home Office... [it] is not for this court.

A very similar line was taken by the Court of Appeal in R v Stark ([1992] Crim L R at 384). In this case the defendant pleaded guilty to possessing heroin with intent to supply. The defendant had been in possession of 27 grams of heroin with an estimated street value of £2,500. He was sentenced to four years imprisonment. Before the Court of Appeal it was emphasised that the appellant had been diagnosed as being HIV–positive some time previously and more recently AIDS had developed. His life expectancy was estimated at between twelve months and two years. It was accepted that his condition made life in prison 'particularly hard'.

The court was asked to reduce the sentence to allow the appellant to be released and to die with dignity, but declined to do so, holding that the appellant's record clearly indicated that there was a grave risk that the appellant would continue to traffic in drugs as long as he would be able to do so. As in Archibald Moore, the court held that it was not their function to manipulate a sentence in such circumstances – it was a matter for the exercise of the Royal Prerogative of Mercy.

The third authority, R v Moore (Richard) ((1993) 15 Cr App R (S) 97) confirmed the approach taken by the Court of Appeal in Stark and held that it was not for the Court `to alter an otherwise proper sentence to achieve a desirable social end'. The latter part of that phrase possibly reflects a more compassionate view of the appellant's circumstances and certainly the Court directed that all the medical reports before them should be forwarded to the prison authorities to effect a consideration as to whether the Royal Prerogative should be exercised in the appellant's favour.

In the later case of James Moore (Court of Appeal, 27^th June 1994), the Court of Appeal did, however, take account of the fact that Moore had “advanced HIV disease” and might need hospice-type care before very long. Accordingly, the court reduced the sentence imposed to below four years, in order to ensure that he would not be categorised as a “long-term prisoner”, meaning that the Home Secretary would have the power to release him on license on compassionate grounds if appropriate, without the need to first consult with the Parole Board.

These decisions, and others concerning the ill-health of the defendant, were subsequently reviewed by the Court of Appeal in the case of R v Bernard [1997] 1 Cr App R (S) 135, where the court made the following statement of principles (pp.138-139). (The case of Wynne, referred to by the court in the extract below, involved a defendant suffering from cystic fibrosis.)

(i) a medical condition which may at some unidentified future date affect either life expectancy or the prison authorities' ability to treat a prisoner satisfactorily may call into operation the Home Secretary's powers of release by reference to the Royal Prerogative of mercy or otherwise but is not a reason for this Court to interfere with an otherwise appropriate sentence (Archibald Moore);

(ii) the fact that an offender is HIV-positive, or has a reduced life expectancy, is not generally a reason which should affect sentence (Archibald Moore and Richard Moore);

(iii) a serious medical condition, even when it is difficult to treat in prison, will not automatically entitle an offender to a lesser sentence than would otherwise be appropriate (Wynne);

(iv) an offender's serious medical condition may enable a court, as an act of mercy in the exceptional circumstances of a particular case, rather than by virtue of any general principle, to impose a lesser sentence than would otherwise be appropriate.

(These principles were reaffirmed and applied in the subsequent case of R v Veiga [2003] EWCA Crim 2420.)

The fourth point is particularly important: in practice it may not matter very much whether a reduced sentence is imposed as an “act of mercy” rather than “by virtue of any general principle”: the result is the same.

The Home Secretary has a statutory power to release a prisoner early on license “if he is satisfied that exceptional circumstances exist which justify the prisoner’s release on compassionate grounds” (Criminal Justice Act 1991, s36). Where the prisoner is a long-term prisoner (sentenced to more than four years), this should normally only be done after consultation with the Parole Board, except in exceptional circumstances.

Some more general sentencing principles which may be relevant should be noted.

There are authorities, for example, that urge leniency where it can be established that an offence was committed in circumstances of severe emotional stress (R v Law, Court of Appeal, 24 April 1975), or where an offence of dishonesty is committed as a result of severe financial difficulties (R v Oakes, Court of Appeal, 4 November 1974); note this was a case where overspending by the defendants' partners caused the financial difficulties.

The courts may also take into account any physical disability or illness which would subject the defendant to an exceptional degree of hardship if sent to prison (R v Herasymenko, Court of Appeal, 12 December 1975). The court may also take into account the possibility that a defendant may be placed in a segregation unit under Rule 43 of the Prison Rules if imprisoned (R v Holmes (1979) 1 Cr App R (S) 233. This latter point may be of significance to an HIV–positive defendant at risk of imprisonment as such a person is likely to be segregated if their health status is known to the prison authorities, but its importance is limited by the fact that the Court of Appeal has suggested that the likelihood of segregation is only a relevant factor where the defendant is exceptionally vulnerable (R v Parker [1996] 2 Cr App R (S) 275).

In very general terms the courts will not take into account the possible adverse effects on immediate family if a defendant receives a custodial sentence (R v Ingham, Court of Appeal, 3 October 1974). This would appear to cause difficulties with mitigation for a defendant who is the partner or carer of a PWA or HIV–positive person. However leniency may be shown as an “act of mercy” where a custodial sentence would clearly cause an unusual measure of hardship. For example, R v Renker (Court of Appeal, 29 June 1976), where the defendant was the carer of a child with leukaemia or R v Haleth ((1982) 4 Cr App R (S) 178) where the defendant was the sole surviving parent of a child with kidney disease.