The accused having to prove their innocence is the way it works in all professional sports.  Why?  Because the crime is based on what is found in the accused's body.  And the accused is responsible for what goes into his or her own body.  With dogs, unlike humans they have no choice as to what gets put in their body.  So the musher, who is responsible for what goes into a dog's body, will now be treated like all pro athletes (with the new ITC rule).  Guilty unless innocence can be proven.  Yes proving innocence will be hard.  But it's hard with all other pro sports.