This week, Utah voters passed Proposition 2 legalizing medical marijuana.

The highly controversial ballot initiative caused Gov. Gary Herbert to announce his intention to call a special session on medical marijuana regardless of the outcome of this week.

The proposition will go into effect on December 1, 2018, and Gov. Herbert’s office announced its intent this week to convene a special session shortly thereafter.

Under state law, an initiative passed by statewide vote can be amended by the legislature after it becomes law.

Gov. Herbert has already discussed changes and compromises with lawmakers and proponents of Proposition 2. This will be the state’s third special session this year.