In New Zealand law, a person accused of a crime is innocent until proven guilty. People who are facing criminal charges have the right to an attorney, who will defend them in court - this attorney is usually a criminal lawyer.
A criminal lawyer needs to examine every detail of the prosecution's case (the case against their client) in order to establish 'reasonable doubt' in the minds of the judge or jury as to whether their client committed the crime. If the defense lawyer can establish reasonable doubt, the client will be found not guilty. A defense lawyer may also try to have their client acquitted of all charges.
Even if a client is found guilty, the work of the criminal lawyer can continue throughout the appeal process. In New Zealand, criminal lawyers practice law in all areas of the North and South island, from Auckland to Wellington, Hamilton, Christchurch and more.
There are different areas of criminal law that a lawyer may specialise in. Some lawyers tend to take on high-profile cases involving serious crimes like murder, manslaughter or sexual abuse. Others take on less sever criminal cases like petty theft. A lawyer's experience and 'track record' in court will likely affect the cost for his or her legal services.