According to this BBC News article, "there have been 609 arrests under terrorism legislation between September 11, 2001 and 30 June 2004. Of those people, 99 have been charged with terrorism-related offences, and 15 convicted."
That's 16.26% and 2.46% respectively. I'm not certain of this, but that sounds a little... disparate. Just why are we arresting so many people that don't get charged, let alone convicted?
Does anyone know what similar non-terrorist-related ratios are like?
Update: Aha, an older BBC article on the issue, and this Muslim news article also sheds some more light on it:
"The Home Office said, "Section 41 of the Terrorism Act 2000 gives the police power to arrest anyone reasonably suspected of being a terrorist or having committed certain offences under the Act. The decision to arrest a person under the Act may be the result of an intelligence-led operation or the result of an officer's judgment in circumstances where he feels an arrest is appropriate."
Nice and specific then. Good to see arrests these days are the result of many manhours of work and careful intelligence, and not just rash decisions being made on the spot.
"There can be a number of reasons for arrests so high in relation to those charged or convicted. For example, where an intelligence-led search of premises is made as part of an investigation, the police may find more than one person there. In these circumstances it is possible that a number of individuals could be arrested and subsequently released without charge because it is not clear at that stage which is the individual sought."
Which explains the more-than-6 to 1 ratio of arrests to charges above. Terrorists! Stop living with other people! Anyone caught swaying government statistics in such an underhand way will be forced to live alone. In a cage.
"Police have to make a decision to arrest based on the circumstances presented to them at a particular time, based on the need to conduct an effective investigation, and above all, to protect public safety."
OK, the bold highlighting was just a ploy to draw attention to the ongoing efforts to draw distinct boundaries between the "good" public and the "evil" terrorists.