First and foremost in our system, everybody deserves a defense. People are considered innocent unless proven guilty. My role is to assess the evidence against my client, prepare a defense based on that evidence and to advocate for my client. My role is not to play judge and jury. The determination of what is to happen to my client, once I’ve done my job, is left to the judge and jury.
It may sound trite, but the role of a criminal defense lawyer is the very opposite of a judge or jury– my job is to not judge. So whether I suspect or even believe I know my client is guilty is irrelevant. I remain objective enough to understand my role in the system and do it to the best of my ability.
Your question is one that is frequently asked of criminal lawyers by people who are not close to the system. But I’ll tell you a question that you could have asked (and one which nobody ever does ask) is “How can you defend someone you know is innocent?” Because when I’ve allowed my objectivity to be compromised and I conclude that my client (notwithstanding the evidence) is actually innocent, my job becomes a hundred times more stressful.