From the second case study it seems the key factor to overcome legal barriers is not to make any mistakes that anyone will ever notice.
We overcame the legal barrier out of necessity really. Lawyers needed to find better ways of dealing with digital information and printing everything out to paper just wasn't cutting it anymore as the data got larger and larger. So, as with many companies, the innovation was born out of necessity and we just happened to see the opportunity and ran with it.
It's still early in the market and law firms need A LOT of help, especially with search, which is unlike most consumer-based search queries (pages of boolean text). Law firms need to make absolutely sure no stone (containing juicy information) is unturned.
Slowly, but surely, law firms will adapt to the needs of the court and their clients, which will bring down more barriers to the legal services domain.