Iowa police officers still operate like nothing has changed in Illinois. You can’t bring marijuana across the bridge from Rock Island to Davenport or from Port Byron to LeClaire.
LeClaire has not changed how they police the bridge and they cannot pull somebody over to check if they have any weed. If the officer has a reason to pull someone over then they can check the car if they either see or smell something.
Penalties are very serious for bringing marijuana into Iowa. It depends how much is in a persons possession and if it appears to be for resale.