Could honesty of IDS encourage Tories to 'go straight' over dodgy crime stats?

Violent crime rose somewhat in the 1980s, sharply in the early 1990s, and has fallen significantly (by around 50%) since the mid-1990s, as the British Crime Survey reports. (The Guardian data blog has the figures, and all of the caveats too).

That is why Mark Easton of the BBC, in a Ten O'Clock News report, challenged David Cameron's claim of "significant increases" in violent crime as part of his "broken society" narrative, and set out why this was factually inaccurate on his blog (which contains a handy graph, and all of the caveats again).

But Chris Grayling doesn't do nuance. So the Tory Shadow Home Secretary has been defending the indefensible today.

The Conservatives have ignored official warnings about the statistics which they are using to send a dossier of "dodgy data" on violent crime statistics to every candidate, encouraging them to claim that crime has risen sharply in the campaign.

For example, the Tory figures claim there were "6015 violent attacks" in Milton Keynes last year, and the local MP put out a press statement last week promoting claims of a 236% rise. "The actual number of people who were victims of serious violence was 81", say the local police, with just over 2000 lower level assaults causing minor injuries.

As The Staggers reports, Grayling is defending the misuse of crime statistics on the grounds that they chime with his sense of people's anecdotal impressions. Of course, the Shadow Home Secretary has form when it comes to hyperbolic fear-mongering over crime, infamously choosing a quiet moment in August to grab headlines by claiming that "in many parts of British cities, The Wire has become a part of real life in this country too."

David Cameron has come under fire on several recent occasions for the cavalier use and abuse of academic evidence and statistics: take this rather restrained Guardian letter from Kathleen Kiernan of York university to correct Cameron's eye-catching misinterpretation of her research, so as to claim that poverty didn't matter to children's life chances if they had confident parents. (Cameron called it ""one of the most important findings for a generation". Kiernan pointed out that the evidence reported that good parenting halves the gap, rather than closing it as Cameron had claimed).

And the Fabians have yet to hear from Cameron's office after writing to him in December to ask for the evidence behind the apparently counter-evidential claims about poverty trends which he made in his Hugo Young lecture.

The Conservatives have talked quite a lot about greater transparency and accountability of statistics and data. They may need quite a hefty nudge in that direction themselves.

So does it have to be like this? It should not be too much to think that there will be some Conservatives who take policy evidence seriously, and would oppose such obvious partisan abuse as the Tory constituency crime breakdown demonstrates.

So congratulations are due to ex-Tory leader Iain Duncan Smith, for his honesty in responding to this crime statistics controversy. The MP and think-tanker told Mark Easton that:

The CSJ has long understood the inaccuracy of directly comparing present crime levels with those published before the National Crime Recording Standard (NCRS) was introduced - which as you note changed recording methods significantly and has rendered direct numerical comparisons with pre 2002/03 levels inaccurate."

David Willetts certainly ought to be another example. His new book praised by The Guardian today. He is one of a number of politicians across the political spectrum, such as Steve Webb of the LibDems and several of the Labour wonks who have gone into Parliament and government, who know their stuff and do seem able to disagree honestly about political and policy choices without needing to twist the evidence.

Here's Willetts-fan Richard Reeves of Demos in Sunday's Observer.

"He's too subtle a thinker to make crude political claims. You can't imagine him, for example, saying Britain is broken. He's the guy who always says, 'It's more difficult than that.'"

Perhaps he could tell his leader that too.

And I notice I am speaking alongside Willetts at an ESRC event on 'making the case for the social sciences' next Wednesday.

With many leading academics present, it could be a good opportunity to see whether those from different political persuasions who want to see good social science inform public and policy debate can agree about how to avoid its abuse.

Let's see whether the Tories will now pledge to drop the use of the dodgy crime figures. Like the broader "broken society" argument itself, they appear to be a prime example of what Boris would call "piffle".