The connection between our recently departed Home Secretary and the world of weblogs might not be immediately obvious, but bear with me here.

I’m not going to rake over the ashes of the Blunkett scandal, but one of the things that struck me is the u-turn in the government’s support for him. The sudden withdrawal of support seems to be connected to comments Blunkett made in his biography, where – and I’m paraphrasing here – he called his colleagues a bunch of incompetent twats who couldn’t hit a cow’s arse with a banjo. Once the comments were made public, Blunkett’s circle of supporters diminished very quickly.

I was reminded of this when I read Queen of Sky’s article, I was fired for blogging. Ellen Simonetti was fired from her job as a flight attendant with Delta Airlines after posting various vaguely provocative photos of her at work, in uniform, on her weblog. While I’m sure there’s some truth in Simonetti’s argument that Delta overreacted, I have to confess that I don’t have a lot of sympathy. She might not have mentioned her employer by name but it was easy enough to guess, and her weblog contained a number of things that Delta no doubt disapproved of. Not just photos taken on company premises in company time, but sarky comments about passengers, moans about particular planes and references to the Mile High Club.

I’m not familiar with Delta’s contracts of employment, but back in the days when I had real jobs every firm’s contract contained two clauses: a prohibition on doing anything that might bring the company into disrepute (including extra-curricular activities), and a prohibition on using company resources for personal things. If you’ve got a day job your contract probably contains similar clauses, and while they’re rarely invoked, they’re still there.

It does look as if Delta’s reaction has been over the top – firing someone without any warnings is a bit extreme – but that doesn’t mean Simonetti is an innocent victim. It’s arguable that her site did indeed bring her employer into disrepute, and there’s no argument that she was faffing around in company premises, on company time, to take pics that were going to end up on her donation-soliciting weblog. I don’t know if that’s against the terms and conditions of her contract of employment, but it’s certainly against the T&Cs of any contract of employment I’ve ever signed.

Which brings me back to Blunkett. The party line from Labour is that Blunkett did nothing wrong, but slagging off his colleagues made his position untenable. Had Blunkett been a normal employee of a company who blogged about what bastards his bosses and co-workers were, he’d have got away with it provided nobody he talked about found the blog and worked out who was posting it. If his identity had been unmasked, he’d have been in deep trouble.

If you intend to blog about your job, it’s important to be very, very careful. You’re rarely as anonymous as you think you are, and if your firm discovers that you’re calling your customers every name under the sun or blogging about the cluelessness of your co-workers, the fact that you’re doing it in your own time is unlikely to mollify the bosses (and if you’re doing it on company time, you’re in even deeper trouble). You should also watch for “no press” clauses: more and more firms’ contracts state that employees can’t talk to the press about company business without prior approval, and blogging may fall foul of that.

Of course, all of this assumes you have a contract of employment in the first place. Many people don’t – particularly temp workers. In those cases it’s even more important to watch your back, because your employer doesn’t need an excuse to punt you.

Blogging about the day job is all about following the golden rule: if in doubt, leave it out. Employees have all kinds of rights, but the right to free speech isn’t one of them.