Take those EPA regulations, for starters. There’s no question Republicans hate them. They will be challenged in the courts—maybe even successfully. But it’s extremely difficult for any new administration to put any of its predecessor’s finalized regulations on the chopping block.

“Assuming you really want to change the policies, that’s going to be hard to do by changing a regulation,” said Cary Coglianese, a law professor at the University of Pennsylvania who leads a program focused on regulation.

The Environmental Protection Agency finalized its regulations implementing Obama’s clean-energy plan earlier this month, after collecting public comments and making revisions for more than a year. To rescind those regulations, a new president would have to start the whole process all over again—taking the time to write a proposed rule, then gathering public feedback, and eventually finalizing a new and contradictory policy. It’s a long road and a hard tactic to justify, regulatory experts said.

“Just the change of administration itself is not a sufficient reason to change a regulation,” Coglianese said.