has written a good piece about why lawyers should create content.
One thing that should perhaps be added to the discussion is how a well run content marketing strategy can help with physical word of mouth recommendations. How it can help people recall your name and company at the critical moment.
With many lawyers their interactions with clients may be at unusual but very important times in their lives (how often do most people file a patent, get divorced or sell a company?). It's likely that they'll remember the lead characters in these events but not necessarily all the characters nor in the vivid detail that you'd hope. More importantly, if your client contact was through a one-off meeting or a networking event, your profile is likely to go out of focus really quite quickly.
If a level of contact is maintained, however, particularly through a medium (like a newsletter) that is of value to the potential client and one that demonstrates your expertise, the chances of them remembering your services rises enormously.