I played this game a long time ago on Armor Games back when flash player was still supported. In this game, the player plays as a group of survivors in a zombie apocalypse that are slowly taking back the city. One of the ways the game can end is when the player researches the cure for the zombie disease. If the player gets that ending, a cutscene plays where a doctor in a full hazmat suit injects a captured zombie with the cure, and the infected is shown turning human again.
Another task that the player can accomplish is to draft a Constitution for the new government.
Does anyone know what the game is?