So what's happened? Researchers neatly summarise the impact of the reclassification of cannabis from class B to class C as "smaller than advocates hoped or opponents feared". The main change of course was that, in most cases, possession of cannabis by those aged over 18 would no longer lead to arrest but to a street warning. Younger people were to continue to be arrested.
OK - what did the researchers look at? There were interviews and surveys with police, young people and the public and they examined policing in four areas - one of which was an area with an active street drugs market.
And our survey said? Most people surveyed supported the move and were aware of the key facts, but not necessarily the finer details, including that 16- and 17-year-olds were still liable to arrest. Police themselves were the least enthusiastic, with nearly six in 10 thinking it was a wrong decision, and some of them complaining that a grey area had been introduced about when to arrest. And it's hard not to sympathise with the officer who reported that sometimes "people are adamant that it is now legal".
So they all wanted a return to arrest?
Not at all. The implication seems to be that some struggle with the degree of flexibility about implementing the law, but others find it useful.
"Many officers" found it inequitable that they were forced to arrest under-18s and would like to decide on a case-by-case basis.
But the picture is inconsistent?
Inconsistent or flexible depending how you view it. In the area with a lot of drugs activity, a positive arrest policy was in place, but in the other three areas warnings had to varying degrees replaced arrest.
Another key aim was to free up police resources - has this worked? The estimation is that, over the three years, replacing arrest with street warnings has saved 269,327 officer hours and hence about 3.5m across England and Wales.
Am I right in thinking things could change again? Much of what happens locally can be determined by guidance from the Association of Chief Police Officers. Guidance released this month says arrest will no longer be automatic for 16- and 17-year-olds, although it may be necessary to arrest a young person in possession of cannabis if they are in or near a place where they may be a risk to other young people, such as a youth club. The guidelines have been welcomed by The Children's Society as "more child-centred" and condemned by the Conservatives as a "dangerous signal".
FACT BOX
- Convictions and cautions for possession of cannabis peaked at 84,310 in 1998. In 2004, the first year after reclassification, there were 45,490 arrests and 27,520 warnings (this latter figure only covers the last nine months of 2004)
- Black and minority ethnic people were heavily over-represented in three of the four areas examined. Researchers say untangling the reasons why is hard but call for trends to be closely monitored
- Policing cannabis as a Class C drug is available on www.jrf.org.uk.
