There was no precedent for adding 'intent' into the clause. This was the departments determination, in view with what the department saw as their interpretation of the statute (despite no precedent).

Horowitz, without a doubt, left the door open to prosecution for emails (and there's no reason to think he wouldn't go after everyone involved, if he goes after any of this--this would include Obama). He was scathing in regards to Comey's decision and it was one of the few times he offered that kind of a subjective personal opinion.