When NFL free agency opens (hopefully next week), the Detroit Lions are expected to primarily be targeting linebackers and cornerbacks. Which position will be the No. 1 need largely depends on if the Lions are able to re-sign cornerback Chris Houston, who will become an unrestricted free agent. If they can't re-sign him, cornerback could very well be at the top of the list of needs.
Even if Detroit is able to bring Houston back, the expectation is for the Lions to take a serious look at some free agent cornerbacks, and the Houston Chronicle's Lance Zierlein reports that their top target will be Johnathan Joseph, although he may not leave Cincinnati.
Sources I spoken to today believe Johnathan Joseph is THE target in Detroit, but that he will stick with Cincy who must spend this offseason
Football Outsiders' Brian McIntyre wrote on ESPN.com that the Lions' first move when free agency opens should be to sign Joseph. McIntyre says Joseph is a "physical corner with solid cover skills who fits perfectly in Jim Schwartz's defense," so the move would certainly make sense.