Below is Missouri's High School Association's by-law that would keep him out of competition until the court proceedings were over with...I can't believe Iowa doesn't have something similar.
2.2 CITIZENSHIP REQUIREMENTS 2.2.1 Citizenship: Students who represent a school in interscholastic activities must be creditable citizens and judged so by the proper authority. Those students whose character or conduct is such as to reflect discredit upon themselves or their schools are not considered “creditable citizens.” Conduct shall be satisfactory in accord with the standards of good discipline.
2.2.2 Law Enforcement: a. A student who commits an act for which charges may be or have been filed by law enforcement authorities under any municipal ordinance, misdemeanor or felony statute shall not be eligible until all proceedings with the legal system have been concluded and any penalty (i.e. jail time, fine, court costs, etc.) or special condition of probation (i.e. restitution, community service, counseling, etc.) has been satisfied. If law enforcement authorities determine that charges will not be filed, eligibility will be contingent upon local school policies. b. After a student has completed all court appearances and penalties, and has satisfied all special conditions of probation and remains under general probation only, local school authorities shall determine eligibility. c. Moving traffic offenses shall not affect eligibility, unless they involve drugs, alcohol, or injuries to others. (Editor’s Note: If a traffic offense is accompanied by an act covered in letter a above, such as property damage, bench warrant, etc., eligibility will be delayed per letter a.)