Hüseyin Çapkın was appointed police chief of his native İzmir Province in 2006. On June 29, 2009, he became police chief of Istanbul Province. On May 13, 2010, Çapkın was appointed province governor of Iğdır.
18 Haziran 2009 tarihinde Resmî Gazete'de yayımlanan ortak kararname ile Celalettin Cerrah'ın yerine İstanbul İl Emniyet Müdürlüğü'ne atandı. 13 Mayıs 2010 tarihli kararname ile Iğdır Valisi oldu.