User blog comment:James12708/Why Exactly is Sheperd on Earth if Arrival Wasn't Completed/@comment-4737548-20121206165858/@comment-4953843-20121206174027

just read conviction.

key words: "so-called terrorist acts ALLEGEDLY carried out by commander shepard"

"councilor udina has PUBLICLY DENIED that the human alliance had anything to do with the destruction of the mass relay"

can take that to mean when shep turned him/herself over s/he simply became the convenient scapegoat (if marines instead of him/her did arrival).

remember that the public in general has very limited information on what really goes on behind the scenes. anderson knows the score which is why his lines reflect as much during vancouver. can't say the same for the common grunt or civilian - so as far as in-universe go they might be under the impression shep blew up the relay even if s/he didn't.

short way of explaining things is simply retcon, but if you prefer consistency without violating player choice here's your beef.