(AP) — Illinois Gov. Pat Quinn will sign legislation making the state the 20th in the U.S. to legalize medical marijuana.

His remarks Thursday will focus on providing relief to the seriously ill, including veterans.

The Chicago Democrat will also tout the legislation’s strict standards, which experts say are among the nation’s toughest. That’s according to a copy of details obtained Wednesday by The Associated Press.

The measure outlines a four-year pilot program that requires patients and caregivers to undergo background checks and sets provisions for state-regulated dispensaries. The proposal says seriously ill patients can be allowed up to 2.5 ounces at a time.

Jim Champion, a veteran with multiple sclerosis who’s advocated for medical cannabis, has been invited to speak at Thursday’s bill signing.