Kern County Sheriff's Department sergeant Gary Williams is under investigation by the District Attorney's Office for failing to book audio recordings into evidence for several cases.

Lisa Green, District Attorney said that Williams may have audio recorded contacts with victims, witnesses, and suspects in some cases without disclosing the existence of these recordings.

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The DA's office said that they believe there are upwards of 40 cases that span from 2006 to 2011 where Williams may have failed to book these recordings.

Green said that criminal cases exist in which there were taped recorded interviews with witnesses and or suspects that were never provided to either the prosecution or the defense.

Green doesn't know if any of the statements that were made still exist.

Public Information Officer Ray Pruitt would not comment on the case, but did say that Williams is still employed with the KCSO and is not on administrative leave.