If the opposing party settled with your insurance, you should be covered from further liability; however, without seeing the indemnification agreement or release, I cannot tell you for sure.
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I am not clear on your question. Did the plaintiffs sign a settlement agreement with you? Did the settlment agreement contain a general release provision? Is there another lawsuit pending against you? You should contact your insurance carrier and ask them to explain your situation to you. You should immediately consult your own attorney to protect your legal rights.
Your question is mixing up civil court matters with criminal court matters. The criminal case settlement can force you to pay "restitution" on the crime. Whether the release the victim signed will protect you from being forced to pay more I don't know without doing some research, but that is a question you certainly need to ask your criminal defense lawyer before making any deal. But in criminal court, there is no such thing as "punitive damages," just fines and restitution. I have no doubt the victim's family signed a release to get the $100K, so you should now be protected from punitive damage claims.
The Vehicular Manslaugther charge, violation of Penal Code §192c.2., is the criminal charge. You should talk to your criminal attorney about any terms of settlement, but "punitive damages" in the form of payment of money is not part of the punishment for conviction of this crime. As noted earlier, there may be a component of your criminal punishment that requires payment of money, e.g., fines or restitution, but these are not "punitive damages".
Your insurance company would not have paid the injured party $100,000 without requiring that he or she sign a Release of All Claims. Such a release would discharge you from any further civil liability, including a claim for "punitive damages." As suggested, you should get clarification from your insurance company as to whether a release was signed.
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