While I dont really agree with the original argument, while what you say is true, I dont think population density was the point. Prison population as a percent

While I dont really agree with the original argument, while what you say is true, I dont think population density was the point. Prison population as a percentage of the total was. Brazil has ~4.2 times higher prison population compared to total. You could argue that compounds with the 1.5 times population density though which would come out to ~6.4 times prison population density. Though 659k vs 3.9k prisoners is a pretty significant difference if you look at it that way.