A criminal lawyer is hired by a defendant to represent them in a court case. While there are a number of responsibilities that a criminal lawyer must undertake, their principle goal is to represent the best interests of the client. That means putting together a case for the defendant that prevents them from being prosecuted.
From the moment that a criminal lawyer is hired, they will start building a case. That means examining all of the pertinent case evidence, interviewing witnesses, contacting experts, and most importantly, trying to convince the jury that the prosecution has not made an adequately convincing argument when it comes to meeting the burden of proof.