I was thinking along the same lines, but rather than assuming Haiti's government is simply lying, I think they are presenting what they detect in their findings.
My biggest issue with some of the data published by the Haitian government is that in Haiti, most of the population doesn't even have some form of documentation or identification. The Haitian government doesn't know that they exist, what their names are, where they live, how old they are, their gender, etc. The population estimates for Haiti have a greater element of speculation than probably of any other country in this hemisphere.
I base this assumption on the large number of Haitian migrants in the DR that lack even the most basic identity documents, such as a Haitian birth certificate or the equivalent of a Haitian c?dula. In fact, this is part of the reason behind the identity crisis within the Haitian migrant community in the DR, since Dominican law requires foreigners to show identity documents issued by their government and then proof of being legally in the DR, before the DR government can offer them or their descendants any Dominican documentation. Plus, Haitian migrants no longer originate from the Artibonite Valley, as was the case for many years. Now they are migrating to the DR from all over Haiti, but the same problem persist.
With a situation like that, you do have to wonder about the data they present, especially since some of their data has changed drastically in the last 2 or 3 years.
Having said that, the Haitian government has to respond to the negative warnings from the US State Department. They are trying to develop some sort of tourism industry, which the country needs very badly, and this type of information is simply not helping. Most tourists will simply not be victims of crime in Haiti or anywhere else, for that matter. These warnings, despite made with good intentions -although there are rumors that the US government tends to be rather harsh against countries that have policies not to their liking, and this is one reason why some people suggest potential travelers to review the warnings from some European governments instead, since they tend to not have this lets call it influence-, simply blow things way out of proportion and causes many more people that would had visited and had a problem free vacation, to not visit.