According to District, Measured, a blog from city's office of the chief financial officer, there seem to be a whole lot more four-legged animals in Washington these days. According to the District Department of Health, dog owners must obtain a license each year for their pet showing that it has been vaccinated against rabies and distemper. The data, which are collected by the Washington Humane Society and District Department of Health, does not account for pet owners who do not comply with the licensing requirements.