A separate case with its own rules
A civil claim for assault or battery is brought by the injured person rather than a prosecutor, and it asks for money rather than punishment. It can go forward whether or not anyone was arrested, and an acquittal in criminal court does not end it, because civil cases are decided on a lower standard of proof. A conviction, on the other hand, can sometimes be used in the civil case to help establish what happened. In New York, claims based on intentional harm can carry a shorter filing period than ordinary negligence claims, although special rules extend the time in some cases brought by crime victims. Waiting for the criminal case to finish before speaking to a lawyer is one of the common ways people lose track of that window.
Who else may be answerable
The person who threw the punch is not always the only party worth looking at, and is often not the one able to pay a judgment. Depending on the facts, a property owner, a bar, a security company, or an employer may face a claim based on its own carelessness, such as ignoring earlier incidents or leaving a known danger in place. Insurance matters here too, since many liability policies exclude intentional acts, and that affects how a claim is framed and who ends up defending it. Medical records, photographs taken soon after the incident, the police report number, and the names of witnesses form the core of either kind of claim. Keep bills and records of missed work as they arrive rather than trying to rebuild them later.
If you are the one being sued
Being named in a civil suit while a criminal charge is pending raises a problem people rarely anticipate. What you say in a civil deposition or a written answer can reach the prosecution, so the timing and content of every response has to be coordinated with the criminal defense. Courts sometimes pause parts of a civil case while the criminal matter is open, but that is not automatic, and a response to the complaint is usually still due within a short period. Ignoring the papers can lead to a default judgment. When we first speak, we sort out which case is moving faster, what deadlines are already running, and whether any insurance policy might respond to the claim.