Witness Interviews may be the best opportunity for a private investigator to develop evidence. One lead generally leads to another lead. This is true of professional witnesses as well as collateral witnesses favorable to your case. Prior to interviewing witnesses, I would first want to consult with you, get your opinion, and develop a potential list. The timing of when these witnesses should be contacted and under what circumstances can be decided. Favorable witnesses can be later deposed or subpoenaed to court by your attorney or can be followed up with by a Guardian ad Litem if one is on your case.