What's the excuse for this shoddiness?

Or is it even shoddiness? Jamie has an excellent piece over at MailWatch on the fact that the Mail has made a catastrophic error in figures about migrant workers. Specifically, it says that in some areas of the country more migrant workers are chasing jobs than locals. Except it doesn't back that up at all:

Unfortunately for Sue, her methodology is catastrophically flawed. She has taken the cumulative total number of National Insurance number (NINo) registrations for the entire financial year 2007-08, and compared it to the number of people claiming Jobseekers’ Allowance (JSA) in the single month of July 2009.

That's a disastrous mistake because there's no legitimate way of comparing the two things - unless you assume that every migrant who applies for an NI number in a certain area (1) stays in that area and doesn't move, either to another area or back to their home country; or (2) doesn't get a job.

Or is it a mistake? That's what I wonder. How did no-one notice, from journalist to printed page, that these figures were so wrong and so misleading? Is it really conceivable that one of the biggest newspapers in the country could make such a spectacularly bad error? Well, of course it is. And I'm no conspiracy theorist. Sometimes people just see what they want to see, and I'm no different.

But there's just something nagging away at me. 5cc in the comments to the MailWatch story points out that the author of this piece is the same Sue Reid who offered cash to Polish people to break the law so she could write a story about the scandal of Polish people breaking the law. Here's a journalist who was quite happy to give people money to break the law in order to create a misleading impression of crime among migrants. What else is she prepared to do in order to get a story into print?