Ok, it's been a while since I did a "let's get this straight" type of post, and this is one I should really have done a while ago.
There seems to be this ever growing misconception that modern witches don't curse. Well that's partially true, as some modern witches don't curse, others however most certainly do.
This belief seems to stem from the fact that in some of the more modern ritualistic manifestations of witchcraft, Wicca for example, things like the Three Fold Law seem to inhibit cursing and hexing. However, not all witchcraft practitioners belong to paths like this. A lot of re-constructionist practitioners will often quote "If ya cannea curse, ya cannea cure!" Meaning to curse is as natural a part of our nature as it is to cure.
Cursing and hexing form a huge part of our magical heritage, from poppets to spoken charms. In years gone by some cunning folk made a living from protecting people against them and undoing them. This is documented everywhere from court records dating from witch trials, right through to the large collection of poppets displayed at the Museum of Witchcraft in Boscastle.
Now don't get me wrong, I'm not suggesting some witches lock themselves away in a tower with flying monkeys reining terror and misfortune over everyone. What I'm saying is, occasionally, usually by way of defense, you need to very firmly take action against someone, and there's no reason that this can't be magical.
It's true, the universe has a way of balancing itself, so randomly hexing people into oblivion will most likely come back and bite you on the backside. However, there is also a school of thought that believes that as a magical practitioner, you can be the means by which balance is restored. In other words, eventually a jackass will annoy a witch, and that witch may well be the source of that persons karmic comeuppance.