It depends on the actual charge that would be filed. Many have extremely long statutes of limitations and some have no limitation. Do not talk to the police or CPS without an attorney.
Attorney Chris Beck
Beck Law Office, L.L.C.
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I agree with Mr. Beck, it depends on the charge. However, most offenses of this nature have extremely long statute of limitation periods. Furthermore, if the offense was alleged to have been committed against a minor, the limitation period may not begin to run until after the alleged victim reaches the age of majority.
However, you have two issues here, one is a concern over potential criminal charges and the other is concern over the use of this information in the custody proceeding. As a result, I would strongly recommend that you consult with an attorney that practices in the areas of criminal and family law who may be able to offer you information on both issues.