The article goes on to mention the privacy issues:
A proposal by U.S. Sen. Bill Nelson to give officers technology used by the military to see through walls is raising eyebrows.
The technology would give officers the ability to see where people are inside a building or house before they go inside.
Nelson said the detector would keep officers safer, but some believe it would be an invasion of privacy.
The idea comes days after two St. Petersburg police officers were killed by a fugitive hiding in an attic.
It also brings into question a person's Fourth Amendment rights, the right to privacy.University of North Florida political scientist Nicholas Seabrook said police would be able to use the devices if they follow very strict rules."If law enforcement want to make use of these kinds of technologies, they need to have a warrant first, and that's a very important distinction within the constitutional sense, whether it's a search with a warrant or a warrantless search, which would be unconstitutional."
Professor Seabrook is probably correct. In Kyllo v. United States, the U.S. Supreme Court held that the use of a thermal imaging device from a public vantage point to monitor the radiation of heat from a person's home was a "search" within the meaning of the Fourth Amendment, and thus required a warrant. That would seem to be controlling regarding the use of a "see-through-wall" radar.