While the Democratic Party hasn’t wholly embraced marijuana legalization, the Republican Party is still seen as the larger opposition force to cannabis in the U.S. Congress. And while most of the party does not support marijuana-related proposals, there are certain members of the leadership who wield more power to kill cannabis legalization laws than others.

Here are eight Republicans most responsible for preventing marijuana legalization laws in Congress:

8. Donald Trump

Technically, Trump doesn’t really have the ability to start or stop legislation in Congress. But his non-committal attitude towards marijuana after taking office has allowed Republicans to continue their prohibitionist policies. If he were to come out and support cannabis legalization, that would put some pressure on Republicans to evolve on the issue.

7. Luke Messer

Messer is the House of Representatives Policy Committee Chairman, which means he’s in charge of placing Republicans on different House committees. This means he has the ability to steer pro-cannabis Republicans away from committees where legalization issues can come up. Messer has consistently voted against marijuana-related proposals while serving in Congress.

6. Kevin McCarthy

McCarthy is currently the House Majority Leader. In this position, he can greatly control when (or if) pieces of legislation receive a vote on the House floor. Despite representing the state of California, McCarthy has consistently voted against protecting marijuana laws in legalized states, and his lack of enthusiasm for the issue certainly contributes to how little cannabis proposals receive recognition in Congress.

5. John Barrasso

Barrasso is a Republican Senator from Wyoming who’s in charge of the Republican Senate Policy Committee. This committee helps research policy and provide recommendations to the party on what pieces of legislation to support. Considering he’s said that the risks of medical marijuana greatly exceed the benefits, we’re guessing his research isn’t providing a lot of support for cannabis legalization.

4. John Cornyn

Cornyn is a Senator from Texas and also the Majority Whip in the Senate, making him the second-highest ranking Republican in that branch of the legislature. He’s routinely spoken out against marijuana legalization, including calling Senator Cory Booker’s bill to legalize cannabis a “big mistake.”

3. Mitch McConnell

Recently, Senate Majority Leader Mitch McConnell introduced a bill to legalize hemp farming. But don’t be fooled: hemp is very different from marijuana, and contains less than 0.3 percent THC. McConnell continues to support anti-marijuana legalization measures.

2. Paul Ryan

While Ryan’s star may be fading as people see him kowtowing to President Trump more and more, he’s still the Speaker of the House and the leader of Republicans in that body. He continues to prevent marijuana legalization measures from reaching the House floor and opposes legalization.

1. Pete Sessions

Unrelated to Jeff Sessions, Pete Sessions is a Texas congressman who has considerable influence over legislation in the House. He’s the chair of the House Rules Committee, which means he can either help or kill amendments to legislation. He’s routinely called marijuana a dangerous drug and refuses to let any pro-marijuana legalization amendments or bills reach the floor.