Apples and oranges. The number in the article is 'crashes caused by officers driving at high speed', the general pop statistic is all vehicular deaths.
Similarly, deaths per 100k is the rate of victimisation amongst the population. Deaths per number of officers is a rate of offending, not victimisation.
It's all about the division at this point. How many cops were there in that region? If it's just Miami-Dade: http://en.wikipedia.org/wiki/Miami-Dade_Police_Department Officers 3,034
soooo.... 3 * (100/3) = 100 deaths per 100k of police population.
Which is 8x the normal rate. It's bad, but it's not too outrageous.