The testosterone limits are the latest attempt to draw a clear line between male and female athletes. In the old days, an elite female athlete would have to verify her sex through genital inspection or chromosome testing, but neither method was perfect. In the gray area between males and females, intersex people may have traits from both sexes. Policy-makers eventually gave up the idea of sex testing, ruling that people should be able to compete in the gender category that they identify with. Testosterone regulations, which came about in 2011 and 2012, are just a newer version of those older, flawed tests, Karkazis argues.