The basic answer is yes, there is a statute of limitations for that crime.
Regarding the length of the statute of limitations, I believe the statute of limitations for threats to kill, under the law, is three years. If charged as a misdemeanor, it's two years. However, as I understand it the level of police interest becomes much less after even a few weeks for a crime like this.
I would suggest you re-target this to the Criminal Defense Practice Area so you can get responses from those who know far more about this than me.
Good luck to you.
This answer should not be construed to create any attorney-client relationship. Such a relationship can be formed only through the mutual execution of an attorney-client agreement. The answer given is based on the extremely limited facts provided and the proper course of action might change significantly with the introduction of other facts. All who read this answer should not rely on the answer to govern their conduct. Please seek the advice of competent counsel after disclosing all facts to that attorney. This answer is intended for California residents only. The answering party is only licensed to practice in the State of California.
The odds of anything happening after this length of time are slim. Having said that, Penal Code 422 is the code for criminal threats. It is a "wobbler" and can be filed either as a felony or a misdemeanor. As a felony, it is a strike and carries up to 3 years in custody.
They would have up to 3 years to file charges against you.
They would have to prove that you made a specific threat of death or harm with the intent that it be taken as a threat.
Don't admit to anything - either here or to the authorities. If something comes of this, you need a lawyer.
You will need a good criminal defense attorney. I'd strongly suggest you find someone who focuses on criminal law and who routinely practices in the court where this case will be heard.
Please pardon any typos - posted via mobile device.
The above answer is for general information only and is based on the information you posted. Every case is fact dependent, so to get a thorough analysis of your situation, you will need to consult face to face with an attorney licensed to practice in the jurisdiction where the incident took place. Do not conclusively rely on any information posted online when deciding what to do about your case.
It seelms unlikely that the boxer will sue you. How are your boxing skills? That would worry me. Maybe you should resolve never to make a threat of any kind again. If by some freak of fate you are charged with a crime, find a criminal defense attorney at once. And hope that no one stabs the boxer.
We do not have a client/attorney relationship until you make an appointment, we discuss your case face to face, I accept a retainer, and we explictly agree to enter into representation.