What are the principles of failure to call a Gang Expert?

Is there any case law where an expert has been charged with misconduct while engaged as an expert witness? (California, United States of America)

Can counsel consult with a medical expert and determine no favorable testimony would result if the expert was called as a witness? (California, United States of America)

Does the failure to provide procedural safeguards at the penalty phase offend equal protection principles? (California, United States of America)

Is a plaintiff's failure to object to the testimony of an expert in a medical malpractice case a strike? (California, United States of America)

Does the failure of the defense to introduce material evidence at trial constitute failure to testify? (California, United States of America)

Does a defense counsel's failure to disclose "statements of experts made in connection with the case" constitute a discovery violation? (California, United States of America)

Does an expert who is an expert in medical malpractice have to produce a declaration of opinion based on hearsay statements? (California, United States of America)

What is the difference between testimony by an expert and opinion by a non-expert? (California, United States of America)

Is an expert's need to consider extrajudicial matters, and a jury's need for information sufficient to evaluate an expert opinion? (California, United States of America)

Is a defendant's failure to object to the testimony of a gang expert forfeited on appeal? (California, United States of America)