From Longman Dictionary of Contemporary Englishdeath warrantˈdeath ˌwarrant noun [countable] 1 SCLan official document stating that someone is to be killed as a punishment2 HARM/BE BAD FORsomething that is likely to cause you very serious trouble, or even your death By indulging in casual sex, many teenagers could be signing their own death warrants.
Examples from the Corpus
death warrant• Magnets are a death warrant to computer disks.• If he does, he is signing his death warrant.• Perhaps that was his death warrant.• Although he did not sign the king's death warrant, he was present at his execution.• I have already signed the death warrant.