Q: In oklahoma, would conversion of estate funds by a co executor be a state crime or a county crime?

A: See

A. Embezzlement is the fraudulent appropriation of property of any person or legal entity, legally obtained, to any use or purpose not intended or authorized by its owner, or the secretion of the property with the fraudulent intent to appropriate it to such use or purpose, under any of the following circumstances:

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B. Except as provided in subsection C of this section, embezzlement shall be punished as follows:

1. If the value of the property embezzled is less than One Thousand Dollars ($1,000.00), any person convicted shall be guilty of a misdemeanor punishable by a fine not exceeding One Thousand Dollars ($1,000.00), by imprisonment in the county jail for a term not to exceed one (1) year or, at the discretion of the court, by imprisonment in the county jail for one or more nights or weekends pursuant to Section 991a-2 of Title 22 of the Oklahoma Statutes, or by both such fine and imprisonment;

2. If the value of the property embezzled is One Thousand Dollars ($1,000.00) or more but less than Two Thousand Five Hundred Dollars ($2,500.00), any person convicted shall be guilty of a felony punishable by imprisonment in the custody of the Department of Corrections for a term not to exceed two (2) years or in the county jail for a term not to exceed one (1) year, shall be subject to a fine not exceeding Five Thousand Dollars ($5,000.00), and ordered to pay restitution to the victim as provided in Section 991f of Title 22 of the Oklahoma Statutes;

3. If the value of the property embezzled is Two Thousand Five Hundred Dollars ($2,500.00) or more but less than Fifteen Thousand Dollars ($15,000.00), any person convicted shall be guilty of a felony punishable by imprisonment in the custody of the Department of Corrections for a term not to exceed five (5) years, shall be subject to a fine not exceeding Five Thousand Dollars ($5,000.00), and ordered to pay restitution to the victim as provided in Section 991f of Title 22 of the Oklahoma Statutes; or

4. If the value of the property embezzled is Fifteen Thousand Dollars ($15,000.00) or more, any person convicted shall be guilty of a felony punishable by imprisonment in the custody of the Department of Corrections for a term not to exceed eight (8) years, subject to a fine not exceeding Ten Thousand Dollars ($10,000.00), and ordered to pay restitution to the victim ...

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D. Any executor, administrator, trustee, beneficiary or other person benefiting from, acting in a fiduciary capacity for, or otherwise administering a probate, intestate, or trust estate, whether the trust is inter vivos or testamentary, upon conviction of embezzlement from the estate shall not receive any portion, share, gift or otherwise benefit from the estate.

A: Title 21. Crimes and Punishments

Chapter 59 - Embezzlement

Section 1451 - Embezzlement Defined - Penalties

It would be a state crime. Counties do not have a separate criminal code.