Law professors love answering these questions!
Seth Weinstein, Esq.
Practicing Criminal Defense in Southern California
This reply should NOT be considered a legal opinion of your case / inquiry. At this time I do not have sufficient factual/legal documentation to give a complete answer to your question and there may be more to the issues you raised then I have set out in my brief reply.
That is not an accurate distinction. There is a distinction (not always clear) between constitutional law and, for example, statutory law. There is a difference (again, not always completely clear) between substantive law and procedural law. But constitutional law can be substantive or procedural. So can non-constitutional law. And courts are not "more forgiving of police mistakes of substantive law," whatever that means. Constitutional law derives more or less directly from, or interprets, a constitution. Statutory law derives from acts passed by a congress or legislature.