Worldwide, non-native English teacher are more numerous than natives*. It is an intuitive fact, but still worth mentioning – especially in light of the fact that a lot of organisations and people adamantly maintain that it is not possible to teach a language one was not born/grown up into. In other words, that only native speakers are able and allowed to teach a language.
Supporters of the native-only dogma argue that non-natives cannot properly teach pronunciation (due to the fact that their own is learned and possibly non accurate), that their vocabulary is smaller and that they might even teach wrong expressions or rules that they themselves have learned incorrectly. Non-native teachers are ineffective at best and downright damaging in some cases.
It’s easy to see the truth in this point of view, and the point made is reasonable. But there’s another side to this coin.
First of all, a lot of non-native teachers know the language extremely well – thanks to the fact that they had to learn it in the first place. They tend to prepare lessons a lot more accurately to avoid exactly the pitfalls that I mentioned above. Furthermore, they can relate to their students a lot better (especially if they share a mother tongue), understand the difficulties they might encounter and help them develop strategies to overcome them – again, because they’ve been through the same. They can be not only a language model for their students, but a learner model as well.
Another point usually made against non-native teachers is that they run the risk to know the language too well, i.e. to end up teaching dogmatically and rigidly and focus too much on grammar. This is indeed a risk, and it is definitely more present for non-native teachers for which teaching grammar is easier than vocabulary or conversation. But this is where the discussion strays into what makes a good teacher, and that’s another story 🙂
*This is true for most languages, although English is of course dominant for both number of classes taught and research, and as such used as an example.