There was that movie. I was thinking the “knockout game”.
There is a movie called “Purge”?
I don’t think knock-out assaults are involved here, as I am pretty sure that there are not white victims.
Okay, you can ignore my question; I found a description of the movie:
The Purge Plot In an America wracked by crime, the government has sanctioned an annual 12-hour period in which any and all criminal activity—including murder—is legal. The police can’t be called. Hospitals suspend help. It is one night when the citizenry regulates itself without thought of punishment. On this night plagued by violence and an epidemic of crime, one family wrestles with the decision of who they will become when a stranger comes knocking.
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Found this description on
http://www.movieweb.com/movie/the-purge