Character mistake: While discussing the death penalty with Mac, Horatio observes that New York hasn't executed anyone since 1976. The last time New York executed an inmate was actually thirteen years earlier, in 1963.
Continuity mistake: After Dave Penrod jumps from the rooftop to escape from Horatio and Mac, the pair reach the ledge far too quickly from where they were previously, at least a building away.
Answer: Yes, sizes of jails differ.