The reason Barry was tested was because he had an obsession with setting fire. Eventually his obsession lead to the death of two people and so was arrested by David Tapp.
Tape: Hello Barry. You are obsessed with fire, an obsession that has claimed the lives of two people. You remember them, don't you Barry, twisting and writhing as their flesh crisped into ash. Now you must face your love of the flame. You have all the tools you need to set the world on fire, but be warned; if you go down this path, it will cost you your life. Give up your obsession and live a full life. Or let the flame consume you.