Hi, I'd like to help you with your question.
It sounds like these kids have learned well from their mother's behavior. Hopefully as they get older, they will gain insight into why this behavior is unacceptable and change for the better.
There is no reason why you and your husband could not limit your contact to cards on special holidays or no contact at all if you prefer. If you are sure that it was all of your husband's children that did these things and not just one or two or even someone else, then limiting your contact to sending cards on birthdays and holidays is not unreasonable. Or you can cut off contact all together. There is no reason you need to be subjected to criminal behavior each time they visit your home or being belittled during phone calls.
What your husband can do is let them know that he has had enough (he should speak for you since they are his kids. If he includes you as the reason why the two of you do not want to see them, they may just blame you for the lack of contact and make their father out to be a victim). He can tell them their behavior is out of control, criminal, etc. He can say he loves them and when they have dealt with their behavior, they are welcome back into your home. If they call your home or phones, change numbers and make them unlisted. Just because they are relatives does not mean you are obligated to be hurt by them.
There is also another alternative if you or your husband are uncomfortable with limiting contact. You can go to therapy together and ask the kids to join you. Talk this out with a therapist and see if everyone could work on the issues that got you where you are right now. Find a therapist by asking your doctor for a referral or if you attend church, ask your pastor for help. You can also search on line at http://therapists.psychologytoday.com/rms/.
I hope this has helped you,Kate