Legal brief?

我是準備拚了老命/小命也要把I140/I485 在十一前自己一並file上去。律師因為時間關係，已經不接手了。不過很多朋友都是自己file的。很多人都認為律師沒有起很大作用。我有點擔心，那個legal brief，也就是律師寫的那個legal document,是個什麽東西？是不是就是律師把我說的話抄一遍？起多大作用？我個人有沒有辦法或必要補救？--- 現在就是要“懵”一把了。有就有，沒有就再說了。

About the legal document
we will write a detailed legal document to persuade the INS that you meet all of the requirements for approval. Our legal memorandum generally exceeds twenty pages, and this is the most important part of the process followed by the expert support letters. Once we complete the draft of this memorandum, we will e-mail it to you for your review and comment. At that time, we will also send you the one form that needs to be signed by your boss. The second legal fee payment is also required at this time.