The first time a citation that has been marked appears in a document is in a footnote it is given a long citation until you mark the same citation later in the text of the brief, then it changes the first citation (in footnote) to a short cite and the
second instance (in the text) to a long cite. The citation in the footnote does not appear in the table of authorities. Why? I believe in the past you marked citations in the order they appeared in the document, and they appeared in the table of authorities.
I reported this "bug" to Microsoft in early March,the technician I spoke with knew immediately what the problem was and said they had just released a hot fix for this issue. He helped me get the hotfix installed and tested with me -- it resolved the issue.
Since we are in a mixed environment, we got the hotfix for both Office 2007 and 2010. Here is a link to the knowledge base article for the hotfix for Office 2010: