getting rid of an abusive person?

my daughter 21 has been in an on off realtionship with a very abusive man. shes charged him, and hes done some time. he dissapears for a while then comes back. she has moved and done everything possible to stay away from him. theres been many restraining orders etc, he just walks right through them, many of the charges just get put off to probation, she has given up on the legal system because he just laughs at it and always gets off with warnings. i fear on day he will really hurt her or worse, the courts dont help at all and im at my wits end,im ready to do something illegal to help her get rid of him. does anyone have any suggestions.? has anyone been in this situation before?? the law is not on her side at all.....help!