Using e-billing tools to help manage expenses and track outside counsel's adherence to guidelines is now pretty much par for the course inside corporate legal departments. But technology alone may not be enough catch errors in law firm billing, a reality that may lead more departments to supplement e-billing solutions with a review by an alternative legal service provider.

"The challenge is the technology can only do so much and you are relying on the lawyers and the law department to review the invoices, looking for flags and then act[ing] on them," said Kevin Clem, chief commercial officer at HBR Consulting.