Question: We're currently hiring for a software engineer position and I've been charged with advancing candidates to the in-person interview stage. We've gotten a number of applications from people who have strong development backgrounds but are recent immigrants from India and China and are very clearly English-as-a-Second-Language speakers, ESL.

We're a really small company and our successful candidate would be the lone developer. In addition to programming, they'll also have to occasionally write content as well as make themselves clearly understood to non-tech people.

As such, I'm leaning towards disqualifying anyone whose English comes across as not being totally fluent. Just a note, I'd disqualify native speakers who wrote poorly as well, but for some reason the fact that most of the applications that would be disqualified on these grounds are non-native speakers feels a little wrong to me.

I'd love for someone to weigh in on the legality of disqualifying obviously ESL applicants.

Answer: 
I am not a lawyer, but I'd say you should make sure that it's not the ESL that's the issue but the ability to write well.

There are plenty of people who can't write intelligible English despite being raised in the UK or US. There are also some/many people who don't speak all that fluently, but may still be able to write well. (I, personally, have a noticeable accent when speaking English and occasionally stumble over words. Hearing me speak, you'd probably know that I'm ESL - but my writing rarely garners that reaction.) So don't focus on whether they're "obviously ESL", instead focus on their written language abilities. 

A lot of places will have some form of programming test for developers. You could just as well have a test of asking them to write the type of documentation you want, and have a non-technical user at your company review it. (If you avoid giving the reviewer any information about the applicant, you are further limiting the risk of accusation of discrimination.)
ESL - English as a Second Language

Having cleaned up my share of poorly written, poorly organized posts from native as well non-native speakers on this site, my attitude is pretty much "a pox on both your houses". 

Since you are mainly interested in the applicant's ability to communicate clearly, request a writing sample. You need not request a writing sample from those who sent you poorly written resumes and cover letter.

I am not going to answer your question as to whether it's legal to discriminate against ESL applicants. I am not a lawyer. The [US civil rights statutes](http://www.justice.gov/crt/about/emp/) say nothing about discriminating on the basis of ESL but they do outlaw discrimination on the basis of national origin. In addition, IRCA (Immigration Reform and Control Act of 1996) doesn't say anything about discriminating about ESL either but [specifically outlaws discrimination against non-citizens with proper authorization to work](http://hiring.monster.com/hr/hr-best-practices/monster-training/security-center/hiring-non-us-workers.aspx). Related story: [John Jay Accused of Bias against non-citizens](http://www.nytimes.com/2010/04/17/nyregion/17johnjay.html?_r=0). In my case, English is not my second or even third language, it's my fourth - being born as a non-European in a Western European country will do that to you :) And it's obvious from my name that I am foreign-born and not so obvious that I am American. 

I think you should sidestep the whole discrimination issue/minefield by requiring a writing sample from the candidates you are interested in. Talking to the candidates would allow you to do further filtering.