Can one give an Aliyah to a person who is deaf and speech impaired? If one listens closely to the person and is used to his speech the words can be understood.

Rabbi Moshe Feinstein in Igrot Moshe Yo"d 4; 49, writes that if his speech can be understood easily he is like any other person but if not – he should not get an Aliya but when needed like his Bar Mitzvah or before his wedding, and occasionally – so he will not feel discriminated or depressed. In a borderline of speech a Talmid Chacham should see this man and decide how to define that specific case.