I'm still working on this, but...
  1. Okay so first, Richard Schiff (who plays Toby) always said it was out of character for Toby to be the one to leak the info
  2. And I always used to believe this as well
    Because Toby sticks by Bartlet
  3. But on the second time watching through the show I noticed something:
  4. Everyone else (Bartlet, Sam, Will, and Josh) betray him at some point in time
    Bartlet lied about MS, Sam left, Will worked for the VP, and Josh becomes obsessed with politics
  5. So, being fed up, Toby decides to leak the info
  7. But because he believes that it is the right thing to do (against everyone else)
  8. And even though everyone else may have betrayed their morals (or really his morals) Toby will stick to his
    By releasing the info
  9. So it is in Toby's character
  10. Because he is always the one to stick to his morals
  11. Even if no one else agrees with him
  12. The end.