Familial Searching

California’s Process

The California protocol includes an agreement between the submitting law enforcement agency and the California Department of Justice. Once the case is accepted by California DOJ, the next step is the search/ranking of candidate offenders. A list of candidate close relatives is produced in accordance with validated criteria. Due in part to the large size of the California offender database (estimated at over 1.3 million), there will always be a list of such candidates, even if there is not a close relative in the database. The list is arranged in order of likelihood that the source of the evidence is a close relative of the offender. There is absolutely no identifying information associated with any of the candidates at this point, they are only identified by specimen identification number. Each time a familial search is conducted, the process eliminates 1.3 million offenders minus the candidate list from consideration. It is agreed beforehand that law enforcement will not have access to the list of candidate offenders.

The next step is to use Y-STR testing to either confirm or refute the likelihood that the candidate offender is a close relative of the source of the evidence. Before the “Grim Sleeper” success, California DOJ had performed familial DNA searching on nine other cases. Using the process just described, no Y-STR confirmation/investigative leads had been produced in those first nine cases. Over 10 million (9 × 1.3 million) offender profiles were excluded from consideration as a candidate relative while they were only ever identified by specimen identification number. In each of the first nine cases, the Y-STR testing of the candidate list produced no concordant results that would strongly suggest the existence of a close relationship. Out of over 10 million opportunities for “genetic surveillance,” none occurred.