I think it all depends on the individual. As long as they are able to go through training, pass the exam and perform their duties as well as any other CNA there should be no problems. There are no laws that would stop them from becoming a CNA as long as they are able to do the job. You may want to take a look at the CNA Skills Check List and CNA/HHA Core Curriculum Requirements to get an idea of what it takes to pass the exam and typical job duties. You should contact the Montana Nurse Aide Registry directly at 406-444-4980 or by email at firstname.lastname@example.org for a definitive answer.