§ 2030.220.Answers in response; form and content; obligations of responding party

This section sets the quality standard every interrogatory answer has to meet, regardless of subject matter. An answer must be as complete and direct as the information reasonably available to the responding party allows, a standard that rules out evasive half-answers dressed up to look responsive while dodging the question underneath. Where a full answer is not possible, the responding party cannot refuse to answer outright; it has to answer to whatever extent it can, supplying the partial information it does have rather than withholding everything because it lacks everything.

Subdivision (c) addresses the common situation where the person answering does not personally know the answer. Lacking personal knowledge is not itself an excuse to leave a question blank. The responding party must say so, but it also has to make a reasonable and good-faith effort to track down the information from other people or organizations under its control or influence, employees, agents, or affiliated entities who might know. That inquiry obligation has one carve-out: it does not apply where the information sought is equally available to the propounding party in the first place, since there is little point making one side dig up what the other side can find just as readily on its own.