There are two broad categories of law with which you might be familiar.
Criminal law addresses the need to investigate crimes, prosecute defendants, and hold offenders accountable, usually through penitentiary, jail or probationary sentences. Common criminal law issues would be driving under the influence of intoxicants, a gun-point robbery of a convenience store, homicide, and rape. The District Attorney prosecutes criminal cases in court, and must prove the guilt of accused defendants beyond a reasonable doubt.
Civil law addresses situations in which people have been harmed, and an economic award might help remedy the situation. Examples of civil law cases include divorce, disputes involving property ownership, and contractual disputes. Private attorneys generally handle both sides of a dispute involving civil law, and the issues in civil court most often need to be proven only by a preponderance of the evidence.
If you have a civil claim – for slipping on an icy sidewalk and becoming injured, for instance – you should discuss the matter with a private lawyer. You can find one listed in the yellow pages under “attorneys.”
If you are a victim of a crime – someone stole your car out of your driveway and wrecked it during a joyride – you should report the crime to law enforcement and the District Attorney’s office will prosecute your case, if possible. You probably also have a civil claim against the car thief, and you should also consider discussing the matter with a private lawyer.