scandal fatigue
The notion of fatigue as weariness and disenchantment with a particular issue or phenomenon dates back to the 1940s in America. Their particular fatigue at that time was in relation to giving donations. It was followed in the next couple of decades by disenchantment with elections and voting (voting fatigue). In a sense these were all things that you could predict that people would find burdensome, but compassion fatigue took a different direction. Who could have expected that we would weary of compassion? In the 1990s we became weary of too much information (information fatigue). And after that we just collapsed under the weight of too many emails (email fatigue) and too much decision-making (decision fatigue).
The latest in this set is scandal fatigue which made a brief appearance in America in the late 1990s but has certainly come back into prominence in the discussions of the reaction of the electorate to Trump. Now we are applying it to our own situation in Australia with a federal election looming, a number of dubious dealings by members of the government revealed, and an apparently apathetic reaction from the public. Does anyone care any more? It seems not now that scandal fatigue has set in.