“The basic purpose of discovery is to take the ‘game’ element out of trial preparation by enabling parties to obtain the evidence necessary to evaluate and resolve their dispute beforehand. Special procedures are available for avoiding loss of physical evidence and testimony of witnesses who may become unavailable (because of death, illness, leaving the state, etc.). Information obtained through discovery may provide the basis for motions for summary judgment or adjudication, and sanctions (which may include the striking of meritless causes of action and defenses). Through effective discovery, parties may find that some claims or defenses are entirely without merit or so lacking in credible evidence that they are not worth pursuing. They may then be induced to stipulate to such matters, narrowing the issues to be tried, conserving court time and reducing client costs. Through discovery, each side can obtain better information regarding the opponent’s case, and thereby better evaluate the strengths and weaknesses of its own case. This increases the potential for pretrial settlement. Effective discovery eliminates the need for guesswork as to the adversary’s case. Each side can find out a great deal about the contentions and evidence the other side will offer. There is less chance of some “surprise” evidence or claim necessitating a continuance. And, there is also less chance for fabrication or forgetfulness by the witnesses who testify, because their trial testimony can be checked against the answers obtained through pretrial depositions, interrogatories, etc. The information sought must be (1) ‘not privileged,’ (2) ‘relevant to the subject matter’ of the action, and (3) either itself admissible or ‘reasonably calculated to lead to the discovery of admissible evidence.’ Admissibility at trial is not required. Rather, the test is whether the information sought might reasonably lead to other evidence that would be admissible. Most discovery procedures are available as a matter of right. No showing of “good cause” or court order is usually required to take a deposition or to serve discovery requests on the opposing party.”
[California Practice Guide: Civil Procedure Before Trial [citations to primary sources omitted]]
