Yes, they can. http://vdare.com/misc/070111_attorney.htm As a practicing litigator for several years, I've had the chance to see countless cases in which the plaintiff (the one doing the suing) is an illegal alien. Yes—illegal aliens can sue! This sometimes comes as a surprise to normal people. One court reporter, told about this during a deposition break several years ago, was so stunned her mouth hung open for several seconds before she could compose herself. "But they're not even supposed to be here," she said, in her working-class New York accent. True. But lawyers have tricks to explain this away. I am not aware of any statistics kept on what percentage of lawsuits in America are brought by illegal aliens. (I also don't know how much it all costs, but the toll on taxpayers, consumers, insurance premium-payers, etc. must be astronomical.) So, you'll have to take my anecdotal word on what I've seen. This is a scandal. Seems it would be pretty easy for a state legislature to stop this practice... but then, it would also be pretty to stop illegal immigration, period, and nobody's doing that.