Puerto Rico has been experiencing a very high murder rate over the past decade or so, reaching record heights in 2011 and still not really falling much recently. Without really going into the specifics of why, I find this post from 2012 interesting in positing that this benefits the interests of the PR government, and that the extent of crime overall (as opposed to murder) is actually not very high. In fact, rape rates are lower than in any state in the US, and have always been - Puerto Rico is one of the safest places in the world for women.
The author of the post compared published crime statistics from the FBI (in the usual place) and from the Puerto Rican Police Department (here, unfortunately still only published from 2008 to 2010), converted to a per-capita basis. And actually, even the overall murder rate in Puerto Rico is "only" as high as the New York Metropolitan area in 1990 (although I should add here that the rate in the San Juan metro area is responsible for the vast majority of the murders on the island, and so it's comfortably higher than NYC in 1990). The author's opinion is that if the Policia were to use the same techniques as the NYPD has used to bring murder rates down, this would have a significant effect, and he's probably right.
It would be interesting to do this same crime rate analysis in a little more detail, and publish it. Data journalism at its best.