Legal Question in Criminal Law in California

Re: Previous non criminal history

Depending on the jurisdiction, a thief who steals $2000 can expect a variety of sentences. In Middle Eastern countries they would cut off your right hand at the wrist. In California you would probably only get jail time and a criminal record so you could never work again.

Re: Previous non criminal history

The prosecutor -- not the victim or the court -- decides whether and when to bring charges, and may do so at any time until the period set in the statute of limitations expires. The victim's attitude about cooperating might influence the prosecutor's decision, but the victim cannot actually force or block a prosecution.

The defendant's criminal history is pretty much irrelevant to whether he will be prosecuted. After all, even the most hardened criminal was a first-time offender at some point. The defendant's record matters most during sentencing, when a judge will generally be more lenient to someone with no record. There are a lot of other factors involved in sentencing, though, and even a first-time offender can get a harsh sentence where circumstances make such a punishment appropriate.

A victim does not have to choose between restitution and prosecution. Even if the thief returns all the money he still committed a theft and can still be prosecuted for it; the difference is that his sentence cannot include restitution if he has already made good on the debt.

Some misdemeanor crimes can be settled through a process called a civil compromise, but the compromise must be accepted by a judge -- and that won't happen until charges have actually been filed and a case opened. Even then, the judge can decline to accept the compromise and can let the case proceed. (Judges rarely do this, but it can happen.) The victim is not obligated to return the funds if this happens. If the thief did not ask the victim to agree to a civil compromise when he returned the money, he cannot force the victim to cooperate in forming one after the fact.

Note for future readers of this answer -- I have answered the question according to California law. The law in other states may be different, especially on the subject of civil compromises.