This wasn't written by Malkin. It was written by Andrew C. McCarthy at NRO. And he raised this issue regarding Article 36 of the Vienna Convention:
That’s it. If the foreign government is determined to educate itself about the case, it must do so by interviewing the arrestee (just like a defense lawyer) or by open source information (just like a reporter or any person curious enough to check the public record). It has no claim on investigative or intelligence information maintained by the United States government. Of course, our government may decide to share more information with the foreign government; but if it does, that is a function of choice, not a requirement of law.
And I posted the text of Article 36 in reply #42. Perhaps you would be kind enough to examine Article 36 and tell me where the government is compelled to tell Mexican authorities anything more than the fact that they have a national in custody.
McCarthy was just working from the Queen of Hysterics script clearly without realizing that there was nothing behind it except a two bit newsletter. It is his embarassment.
No one has claimed that treaty implementation always provides only the minimum required. Cooperation between friendly nations extends beyond the minimum required though in this case there has not been much more extended.
Of course, those of you who prefer to get their information from sources with no authority and little credibility could care less about any fact which does not fit in with the Obsession.