If he is being tried for armed robbery, he needs to have an experienced criminal
defense lawyer to represent him since the sentence
for armed robbery could be 10 years in prison or more. If he cannot afford a criminal defense lawyer, then a public defender will be appointed to represent him. I cannot tell you his best course of action because I do not know the facts, his testimony, his alibis, the credibility of the witness, and surveillance, etc. My advice may be different in one situation than in another situation. My answer to your question is he can be convicted even if the only testimony is one eye witness. Good luck.
I hope that I have helped you and that I have answered all of your questions. Please
ask more questions if I have not answered all of your questions.
Please be aware that my answer is not legal advice, it is merely information.
You and I have not entered into an attorney/client relationship, and I am not
responsible for your legal rights. The only way for us to be in an
attorney/client relationship is if you have signed a written retainer agreement
with my law firm.