Donna,
As a child of two parents who were new immigrants to this country and lived with church members, I have to say I am a little offended at the previous answer to your question. While I understand that there is risk, the truth is there is risk to any tenant, no matter how "new" they are to the country. There are always "unknowns" about any tenant, and it is my belief that these "unknowns" are the reason why not everyone gets into real estate. My parents and their friends were all new immigrants who never took being in this country for granted and without the help and generosity of the people they first met when they got here, would not be the successful tax-paying home-owners they are now.
With regards to the new immigrants you are screening, I would recommend getting more details with regards to jobs and how they will be paying their rent. If you are being paid directly by the government body, that is a definite bonus. Even better if they already have jobs. My experience with tenants on social assistance (not new immigrants and we were not paid directly) has been split right down the middle. One set of tenants were absolutely awful and the other, although they pay late occasionally, always pay their rent. Make sure you meet them and their family and use your own judgment. Think about the type of tenants you want for your property and see if they fit that criteria and if you do end up accepting them (and should do this with any tenant), make sure you outline the rules very clearly (i.e. you will send a notice the day after rent is due if rent is not paid).
Caitie