This agency should only work in fictional stories.
"Don't Talk To LEO" no matter how friendly they MAY SEEM. EBG
If you've never noticed, Indy Public Safety (Now Homeland Security) has a number of SUVs. For the FD and the folks who used to be Emergency Management responders, the justification for 4WD vehicles was to make it possible to get around in bad weather, and larger size vehicles allowed for the various types of gear needed for emergency response and personal protection. Police Departments in our environment generally have at least one or two for the same purpose.
For the Feds, pretty much the same reasoning applies, especially for supervisors or officers who have specialized equipment. As was said upthread, the cost via government bulk purchase contract isn't substantially more than a similarly equipped sedan.