Drug OD/ Murder charges

I live in a relatively small town that has recently had multiple overdoses. The user has bought meth I believe that was laced with fentanyl. This has caused massive fighting on local news website’s wether the man who sold these users the drugs should be charged with murder. In the case of a libertarian ideology that normally believe in suing of anyone that interferes with your life liberty and property. Should the family of the people that over dosed be able to sue the drug dealer? Or is it more the ideology of you as an adult willingly bought drugs and took the risk. The idea that you could have used those drugs in a safe manner and wouldn’t have not over dosed with property dosage? And if you believe that there should be a murder charge what degree? What if the dealer’s knew it had fentanyl. Fentanyl at very very small doses is safe. So first degree would be out unless the dealer’s “spiked”. But again you knew the risk and bought street drugs..?