I think she does contribute to her bad image but I can't help thinking that pressure from the press (give a dog a bad name) doesn't help. She might do something useful every now or then but doen't get reported because its not 'the image'.
Obviously being followed around 24hrs a day just in case by the media.
Lindsay is responsible for her bad press. There's an old saying, "if you don't want to get bombed, stay out of the target area". She needs to get out of the limelight and stay out of sight if she ever hopes to repair her reputation. Almost every day is another nightclub, shopping spree, altercation of some sort. The paps may be following her around, but she's always somewhere to be caught out. Clearly she isn't very bright if she hasn't yet figured this out.