Curious question that I've often wondered but never really dug into... does a defense attorney generally know whether their client is actually guilty of the crime they are charged of? Or how does that work? I cannot imagine having motivation to build a defense case on someone I knew was guilty. But I also can't imagine the not knowing and trying to build a case. Any attorneys here to shed light?
It depends. Your job is to represent your client's rights and interests in the proceeding against him or her. Attorneys talk about a "knowledge problem." You can't participate or assist your client in an ongoing crime or fraud. That's where it gets tricky - if your client tells you they did something, you really have a problem letting your client get on the stand and perjure themselves. I think that's the biggest problem that comes up for defense attorneys in trying to navigate the "did they do it?" question. But you definitely don't have an obligation to tell your client to confess because it's the state's burden to prove the case. Your client has a right to stay silent, no matter what they did or didn't do, and see if the state has the evidence to establish the claims they're making. Many times they do with all the new CCTV and scientific evidence. So I don't know any defense attorneys that feel like they should be doing the state's job for them or feel guilty about making sure your client's rights are being respected.
Some defense attorneys focus on the system. If no one checks the state, the state will be out of control and we all will suffer for it. Some attorneys focus on the humanity of their clients (in many types of crimes). You're not defined by the worst thing you've done and you should have an opportunity to do your time, turn your life around, and contribute positively to society.
I don't know anyone that is like, heck yeah, guilty client, let's pull a fast one on the state. Defense attorneys talk much more about accepting that sometimes the facts are bad and you have to do your best.
Personally I focus on making sure the client understands the proceedings and understands the evidence against them. These are complicated proceedings with well-educated and well-paid people on all sides and it is important to me that the defendant understand and be able to participate. In many cases, it's trying to explain mitigating circumstances and why this person should receive lesser charges and a lighter sentence. It's advocating to get your client to Drug Court to deal with addiction. It's getting your client into Veteran's Court to deal with PTSD and get services they are entitled to.
I have had cases where I don't believe the act charged, like unauthorized access to a computer, should be a crime. I don't care if my client did it or not because I don't think the state can actually prove that the actions alleged meet the elements of a crime and I will fight those cases to avoid bad decisions.
So I guess this is really just a long way of saying the most lawyerly answer of all: "it depends"