That's kind of why our justice system is innocent until proven guilty. Until it's justified to believe someone is guilty, we'll assume they are not.
No, we do not assume that they are innocent - that is ridiculous. If we assumed that someone were innocent, we would not be investigating them, gathering evidence, and seeking prosecution.
In general, don't hold a belief until it's justified. So I'll ask again, what unjustified belief is it you think I have?
Easy. You cannot reasonably justify the belief that no diety exists in the universe because we have yet to even barely understand the universe. And before you cling to the, "I simply lack the belief" line, I could just as easily claim to be an agnostic theist and start this circle over again.