Lohan, like Paris, willingly does stupid shit like this because she knows (and does) she can get away with it. Both women are filthy rich and can just hire a driver to take them home after partying but no, it's the thrill of getting away with murder that compells them to do this.
The solution is simple, set an example by putting her in jail for a reasonable amount of time so she'll get the message to not do this bullshit again. It's a fucking joke how someone can drive drunk while she's on probation and someone who had cocaine found in her trunk twice on two separate occasions to just walk off free as if nothing happened. If the law was actually enforced then this shit wouldn't happen. If this was a normal joe then obviously, he'd be facing a heavy sentence by now.