2023 Washington Code 28B.20.502 – Medical cannabis research

2022 Washington Code 28B.20.502 – Medical cannabis research

2020 Washington Code 28B.20.502 – Medical marijuana research

2019 Washington Code 28B.20.502 – Medical marijuana research

2018 Washington Code 28B.20.502 – Medical marijuana research

2016 Washington Code 28B.20.502 – Medical marijuana research

2015 Washington Code 28B.20.502 – Medical marijuana research

2014 Washington Code 28B.20.502 – Medical cannabis research

2013 Washington Code 28B.20.502 – Medical cannabis research