2024 Iowa Code 509A.4 – Participation optional

2023 Iowa Code 509A.4 – Participation optional

2022 Iowa Code 509A.4 – Participation optional

2020 Iowa Code 509A.4 – Participation optional

2018 Iowa Code 509A.4 – Participation optional

2016 Iowa Code 509A.4 – Participation optional

2014 Iowa Code 509A.4 – Participation optional.

2009 Iowa Code 509A.4 – Participation optional