Wrongful death claims are based on the legal tort of negligence. Wrongful death negligence claims must prove four things to be successful: duty, breach, causation, and death.   The law is clear that a defendant(s) (the person(s) responsible) must breach a duty of reasonable care before an injured person can recover money damages.  Reasonable care means that degree of care that a reasonably prudent person would use under the same circumstances.  The clearest example of this is if a driver who is speeding strikes another person and causes that person to die. In this example the driver owed a duty to keep his vehicle under control, but when he did not, he breached his duty to other people on the roadway and caused the death of another person.
With regard to medical negligence claims, under New York Law, to prove a medical malpractice case there must be expert medical support for the action. The wrongful death medical malpractice lawyer must be able to prove that the doctor or hospital breached a duty of care to the patient by providing poor care, or failing to properly diagnose a condition and as a result of that caused the death of the patient.