When politicians’ historical crimes catch up with them, what happens to their statues?

Lenin and Stalin in the Soviet Union, Chiang Kai-shek in Taiwan, and King George V in the United Kingdom were all the subject of a huge number of impressive statues and monuments. They were also associated with some rather heinous historical events: the Red Terror (Lenin), the Great Terror (Stalin), the White Terror (Chiang), and the British Raj (George). As their history was laid bare, what would become of the statues?
On one hand, these are monuments to oppressors, dictators, and despots. On the other hand, they are art, and they are history, and we forget such history at our peril. A few countries around the world worked out a compromise: gather the statutes together. Put them in context. Remember history, but don’t glorify it. These are the statue graveyards.
Memento Park, in Budapest, is full of Communist statues like the one pictured above. The statuary part of the park is called “One Sentence About Tyranny” Park. It’s named after a poem by Gyula Illyés that ends like this:
because from the first,
One Sentence About Tyranny
tyranny stands there at your grave,
it decides who you were
and even your ashes serve it
Lithuania has a similar installation, Grūtas Park:

The statues of viceroys, emperors, and empresses of the British Raj are collected in Coronation Park in Delhi. (Incidentally, on the same site where those British rulers of India were first proclaimed.) Moscow has a Fallen Monument Park.
Taiwan is full of bronze statues to Chiang Kai-shek (around 40,000 at last count). Because of recent re-evaluations of his rule, a couple of hundred have been relocated to the president’s temporary mausoleum, in the so-called Garden of the Generalissimos:

(Why is it a temporary mausoleum? Well, Chiang wanted to be buried in his home town in mainland China, when the country was reclaimed from its Communist leaders. It looks like he’ll be waiting a long time yet.)
[Thanks to David S.]