UK politicians and their expense claims

For those of you not following the UK news, the UK's House of Commons is currently undergoing a bit of a scandal. It turns out that a bunch of MPs have been claiming unnecessary expenses. Such as:
16,000 pounds on a mortgage which had ended
2,200 pounds on having his house's moat cleaned
41,709 pounds on second home allowances

The BBC lists the total to be repaid as 123,283 pounds and 50 pence. That would fund my workplace for a year. That's a lot of money. Now, while I'm not anti second home expenses for MPs, after all, many workplaces provide relocation expenses, I do think that a lot of these claims are unbelievably corrupt.

So, as well as sacking the idiots, which everyone seems to be baying for, why aren't we holding the civil servants who signed the claims off to account? Whose decision was it to put through a claim for Douglas Hogg to clean his fucking moat?

Sack the guy (I presume it's a man - there aren't many women in the head roles in the civil service) who is in charge of the departments that processed the claims. They are just as responsible.