He tested positive for mar1juana AND it was a diluted sample meaning that he was trying to cheat the test. When you try to cheat the test, it's an automatic fail, the presence of mar1juana, even the tiny amount they found, just shows that he had reason to try and cheat the test.
http://www.tmz.com/2016/04/13/johnny-manziel-alleged-hit-and-run-josh-gordon/ These guys should just accept that they're out of the league and start a reality show together. I promise y'all it would be super entertaining. "The Josh n' Johnny Show!"