As I do not practice law in Iowa I am only providing general information and I am not providing legal advice. Please do not rely on this information. Use it as a jumping off point for a discussion with a lawyer in your home state.
Iowa Statutes of Limitations on Criminal acts are codified in code section 802.1 et seq
For Felonies the Statute of Limits is as follows:
1st and 2nd degree murder: none; others: 3 yrs.; 1st, 2nd, 3rd degree sex abuse committed on or with a person under 18: within 10 yrs. after victim turns 18; other 1st, 2nd, 3rd degree sex abuse: 10 yrs; incest with person under 18: within 10 yrs. after victim turns 18; sexual exploitation by counselor or therapist: 10 yrs., unless victim under 18 yrs., then 10 yrs. after victim turns 18; fraud or breach of fiduciary duty: extension up to 3 yrs.
For Misdemeanors the Statute of Limits is as follows:
Serious misdemeanor: 3 yrs.; simple misdemeanor or violation of ordinances: 1 yr.
The Statute is tolled if the accused is not in the state.