Eviction in New York does require a 72 hour notice from the Marshall.  If your landlord locks you out of your apartment you can go to your local police department  for re-entry.  If the police do not help you re-enter your apartment then you must seek the court's help by requesting an order show cause to restore possession in housing court.

This is not legal advice, but merely general information.  In no way should this be considered as legal advice.  You should contact an attorney in your licensed in your state to discuss your rights.