> You might argue that defense lawyers have disincentives to adopt technology that would reduce billable hours, but what about the other side of the v.?

The US has a vast oversupply of lawyers (sure, star litigators make lots of money because they are in short supply, but they aren't the people whose labor legal technology aims to replace), which makes the value of reducing legal gruntwork low, plus to replace legal grunts using WestLaw or similar tools, you've got to either build on top of one the handful of such tools or duplicate it's corpus of annotated data and the massive infrastructure dedicated to keeping it current before you even get to the novel part of your tool, or you won't have anything usable.

So, it's a super high barrier to entry for a market where you are competing with cheap, abundant human labor.