They didn't have an effective enforcement apparatus. The courts were frequently corrupted. There were no effective fines. So the rules were there, but enforcement was practically null. They realized after some time that they didn't have the whole package, and they couldn't make it work.
Charges are very different.
A charge says basically we're not treating this as a criminal problem. We're saying that you're costing the environment by polluting. You're costing us by polluting, and that's something you're going to have to pay for. The more you cost us, the more you're going to pay. Every unit of your pollution, you'll pay for.