Federal agents tried to track David Streever to his home and hotel, and left him a warning notice that a critical email he sent the former head of ICE may have been illegal. Now he's suing.

ICE says David Streever’s email about the murder of two American citizens in Minneapolis was actually a threat.

Federal agents tried to track David Streever to his home and hotel, and left him a warning notice that a critical email he sent the former head of ICE may have been illegal. Now…