|CHAPTER 6 RECREATIONAL USE OF CANNABIS
6.1 Cannabis is by far the most widely used illicit
drug in the United Kingdom, as in most other Western countries; and almost all of this use
is for recreational rather than medical purposes. According to the Department of Health,
"Cannabis is now the third most commonly consumed drug after alcohol and
tobacco" (p 47).
6.2 Cannabis dominates the drug crime statistics,
and the figures are rising. Figures for the whole United Kingdom for 1996 (Home Office
Statistical Bulletin 10/98) show that 72,745 drug offenders (77 per cent of the
total) committed offences involving cannabis (alone or with other drugs). There were
91,432 seizures of cannabis in 1996 (75 per cent of the total for all drugs) and this
involved record quantities of cannabis resin (66,921 kg), herbal cannabis
(34,373.6 kg) and cannabis plants (116,119 plants). These figures, which are the most
recent available, represent more than a threefold increase over 1990, with a
particularly sharp increase in the number of offences related to the cultivation of
cannabis plants and the numbers of plants seized.
6.3 It is difficult to put a figure on the
prevalence of cannabis use in the United Kingdom. The Parliamentary Office of Science and
Technology, in their Cannabis Update of March 1998, gave figures from the British
Crime Survey 1994 which indicate that in the adult population (16-59) 1 in 5 had
"ever tried" cannabis (1 in 20 within the previous month) and in the 1629 age
group just over 1 in 3 had "ever tried" cannabis (1 in 20 within the
previous month). These figures are not dissimilar to those in the WHO report for other
countries in Europe, with somewhat higher
figures for the USA, Canada and Australia. They suggest that as many as 7.5m people aged
16-59 in the United Kingdom have used cannabis at least once, and that between 1.5m and 2m
take the drug at least once a month (cp Montgomery Q 559). The Royal College of
Physicians have established a Joint Working Party with the Royal College of Psychiatrists
which among other matters will review the epidemiology of illicit drug use in the United
Pattern of use
6.4 The pattern of cannabis consumption in the
United Kingdom varies according to geography, socioeconomic conditions and the age of
the user. Professor Edwards observed that cannabis is and has been used in very
different ways in different times and places; for instance, there are people in south
London who smoke 20 joints a day (Q 26). Dr Robson cautions that much of the use
of cannabis in the community does not come to the attention of the health services or the
police, and therefore little is known about it (Q 456).
6.5 The Independent Drug Monitoring Unit conducted
a survey of 1,333 regular cannabis users who attended a major pop festival in Britain in
the summer of 1994 (p 231). The majority were daily cannabis users with an average
consumption of about 24.8g of cannabis resin per month. Respondents gave highly positive
subjective ratings to cannabis (as opposed to negative subjective ratings to solvents,
cocaine and heroin). More than 60 per cent believed that cannabis had been of benefit
to their physical or mental health. They would prefer that the law was more liberal, but a
majority (70 per cent) did not think that they would use more if it was.
6.6 Dr James Robertson, a GP working in
Edinburgh, has reported the results of a survey (funded by the Royal College of General
Practitioners) of 328 consecutive patients attending his surgery (average age
33.7 years). 200 patients
(61 per cent) said that they had used cannabis at least once, and more detailed
interviews of 101 of these revealed that 90 were regular users, with 67 using cannabis on
a daily basis. Most spent £25 or less per week on cannabis, but a small number of
individuals spent £100 or more per week.
6.7 Neil Montgomery described for us various ways
to take cannabis recreationally (QQ 544-554). He divides recreational users into
Casual Irregular use, in amounts up to 1g of resin at a
time, to an annual total of no more than 28g (Q 545);
· Regular Regular use,
typically of 0.5g of resin a day (equivalent to 3 or 4 smokes of a joint or pipe), adding
up to about 3.5g per week (Q 548);
· Heavy More or
less permanently stoned, using more than 3.5g of resin per day and 28g or more per week
(Q 554). The smallest group, around 5 per cent. "The extent to which a
heavy user can consume cannabis is largely unappreciated."
Herbal cannabis appears to be consumed at twice the rate of cannabis resin, presumably
because of its lower content of THC. Comparable data are provided by IDMU (pp 2313).
6.8 According to POST's Cannabis Update,
9 per cent of ever-users use cannabis daily, and 14 per cent several times a
week, making it of all illegal drugs the one most likely to be used regularly. According
to Professor John Strang, Director of the National Addiction Centre, few users end up
in hospital with acute psychiatric problems, and most regular users are not nowadays
advised by their doctor to change their habits (Q 244). For the risk of dependence,
see Chapter 4.
6.9 Many cannabis users also consume a variety of
other psychoactive agents. As the commonest method of using cannabis in the United Kingdom
is to smoke cannabis resin mixed with tobacco, nicotine use is very high among cannabis
users. Among other things, this makes it difficult to assess the respiratory risks of
smoked cannabis as they are confused with the well-established risks of smoked tobacco.
Alcohol use is also common, but regular cannabis users may consume less than non-cannabis
users. Drug treatment clinics often see poly-drug users, who are consuming a variety of
illicit substances, of which cannabis is commonly one (QQ 42, 216, 487, 515, 562; DH
6.10 According to the Department of Health, most
cannabis users have discontinued by their mid to late 20s (p 46); and of those who
have ever been daily users, only 15 per cent persist with daily use in their late 20s
(p 45). Neil Montgomery has identified a group of regular users who stop in
their 30s and start again in their 50s (Q 575).
Content of cannabis consumed in the United Kingdom
6.11 Some of our witnesses expressed concern that
the preparations of illicit cannabis used in the United Kingdom today are more potent than
previously, exposing users to a greater risk of acute intoxication and long-term adverse
effects. Professor Ashton (p 12) suggested that "a typical 1970s `reefer'
contained about 10mg of THC..., while a typical `joint' today may contain 60-150mg or more
of THC. This increase in potency results from sophisticated plant breeding and cultivation
methods leading to highly potent varieties of cannabis, such as Skunkweed". Other
witnesses made similar assertions (e.g. Q 33).
6.12 However, the Home Office Forensic Science
Service, who have data on the THC content of seized cannabis samples, do not support the
view that most users in the United Kingdom are exposed to material containing ten times as
much THC as in the 1960s and 1970s. They say, "Cannabis resin...has a mean THC
content of 4-5 per cent, although the range is from less than 1 per cent to
around 10 per cent. This pattern has remained unchanged for many years" (p 218).
Cannabis resin, imported most commonly from Morocco, Afghanistan or Pakistan (IDMU p 230),
is the form of cannabis most widely used in the United Kingdom, and accounted for two
thirds by weight of all seized material in 1996 (Home Office Statistical Bulletin
10/98). One of our witnesses, a user and convicted dealer, claimed that most modern
cannabis is in fact weaker than material from the 1960s.
6.13 On the other hand, there appears to have been
an increase in the THC content of herbal cannabisprobably because of the use of new
strains of cannabis plant and improved growing conditions. In the United States, the
University of Mississippi have analysed the THC content of seized cannabis on behalf of
the US government since 1980 (see Appendix 4, paragraph 13). They report an increase in
the THC content of herbal cannabis from around 2 per cent in 1980-81 to more than
4 per cent in 1997. The Forensic Science Service report that herbal cannabis in the
United Kingdom currently also contains an average of 4-5 per cent THC. They also report
that cannabis grown in the home, using improved growing techniques and improved plant
varieties, now produces herbal cannabis with a considerably higher THC content, with an
average close to 10 per cent THC and a range extending to over 20 per cent
(p 218). Use of "hydroponic" cannabis (grown in a nutrient solution rather
than in soil) appears to be increasing rapidly, with plant seizures in the United Kingdom
up from 11,839 plants in 1992 to 116,119 in 1996.
6.14 Professor Hall suggested, "More potent
forms of cannabis need not inevitably have more adverse effects on users' health than less
potent forms. Indeed, it is conceivable that increased potency may have little or no
adverse effect if users are able to titrate their dose to achieve the desired state of
intoxication. If users do titrate their dose, the use of more potent cannabis products
would reduce the amounts of cannabis material that was smoked, thereby marginally reducing
the respiratory risks of cannabis smoking" (p 221; cp IDMU p 235).
6.15 The overall quality of imported cannabis resin
appears to have fallen in recent years; many users perceive cannabis resin as adulterated
and forensic analysis frequently confirms that this is the case, with the addition of
caryophyllene, a constituent of cloves, being particularly common (IDMU p 230; Montgomery
p 132 and QQ 577, 589). Yet Professor Hall considers that concern about
herbicide contamination is unfounded, and that case history evidence of health problems
from microbial contamination is limited. Neil Montgomery calls for research in this
The state of the law
6.16 This Government show no sign of taking a
softer line against recreational use of cannabis than their predecessors. According to the
White Paper Tackling Drugs (Cm 3945) of April 1998, "The more evidence
that becomes available about the risks of, for example, cannabis...the more discredited
the notion that any of the substances currently controlled under the 1971 Act are
harmless". This echoes the view of Professor Edwards of the ACMD: "We are in a
rapidly changing field of knowledge"; and new knowledge is making cannabis look more
dangerous, not less (QQ 21, 27).
6.17 Most of our professional witnesses agree that
the adverse effects of cannabis fully justify prohibition (e.g. Henry/RCPath p 224).
The only argument on the other side is that cannabis is arguably less dangerous than
alcohol or tobacco (e.g. RCGP p 281, Kendall p 268). Professor Hall
acknowledged this, but noted "the difficulty in predicting the effect that relaxation
of cannabis prohibition would have on current patterns of cannabis use and the harms
caused by that use" (p 222).
6.18 The Under-Secretary of State at the Home
Office, George Howarth MP, told us confidently that legalising recreational use would
cause such use to increase (Q 674). Professor Edwards, writing for the Royal
Society, is less sure: "We would expect weakening of controls over cannabis to result
in increased use levels, but this is an empirical question on which research at present is
not conclusive...Removal of prohibition on cannabis would have to be described as a voyage
into the unknown. Some added harm and some added costs would undoubtedly result"
(p 303). There is international experience which might throw light on this question,
but we have not explored it in detail.
6.19 We have not considered the wider range of
social and criminological issues which would be raised by any proposal to change the law
on recreational cannabis use. These include enforcement, the impact on use of other
illegal drugs, and the international context and the danger of "drug tourism";
as well as ethical, philosophical and religious questions about the freedom of the
individual, the nature of society and the morality of mind-altering drugs. As we said when
we began this enquiry, these matters fall outside our remit as a Science and Technology
Committee. An Independent Inquiry into the Misuse of Drugs Act, chaired by Lady Runciman
of Doxford and supported by the Police Foundation, is currently considering the matter in
its wider context; they expect to report next year.
23 See also the Annual Report on the State of the
Drugs Problem in the EU 1997, by the European Monitoring Centre for Drugs and Drug
24 Br. J. Gen. Pract. 1996, 46, 671. Back