Well, I've had a different experience. More than once. So I'd say it's not that extremely unlikely.
Maybe my lawyer has a really old version of Word or something and he keeps sending me files in an old format that isn't supported as well.
I've also had a lot of files opened flawlessly by LibreOffice; it depends on how many features you're using. Maybe you're trading documents that aren't that complicated?
Word has its flaws, yes, just like anything else. Still, I've tried every other thing available, and nothing comes close.
You see, it is the word processor for all the non-techie people out there. They have no idea how to properly use it (and pc's in general), so they blame Word for all their faults.
LibreOffice, on the other hand, has much more competent userbase (in average), and despite the lack of certain features LibreOffice has more positive image.
It would be helpful if you could indicate what is missing or what you mean by correctly importing.
If there are no detailed Word error messages or diagnostics, perhaps you could ask your lawyer to send you a PDF or paper version, so you can tell if there are any differences.
I for one would be very attentive to the possibility of missing or incorrect information in legal documents...
Are you sure your lawyer is even using Word? Many still use word perfect. I was just at the office of a state legislature yesterday and they are 100% a word perfect shop.
In my experience, OpenOffice/LibreOffice screws up non-trivial formatting on import, and Microsoft Office screws up non trivial embeddings from previous versions. I've had both screw up old Word documents.
I prefer LibreOffice when I need to open old files -- the format is often botched, but all the content is always there -- which was not my experience with Microsoft Word.
Also, in my experience LibreOffice will happily open documents Microsoft Office complains about as being corrupt.
I don't say it's not possible at all, but extremely unlikely.