Matt Finn's interview with Sheriff. Sheriff is clear that he has no problem working with the FBI and that he's using the FLA lab because all of the evidence already gathered--including NG's DNA--is at this same FLA lab his office has used long before his tenure as Sheriff.
This case is the Sheriff's jurisdiction. Sheriff says he has the FBI in charge of Ransom note because they have the expertise. Sheriff says he doesn't have a problem with FBI.
There appears to be a FBI person who is unhappy that this is the Pima County Sheriff's jurisdiction rather than the FBI, and is taking the focus off of the investigation by telling multiple media sources that the Sheriff is withholding key evidence from the FBI.
Sheriff isn't withholding key evidence from the FBI but rather is using the same lab that they have used for NG's DNA and other evidence in this case so that results of the gloves can be compared with the other results the FLA lab already has.
No saying this Sheriff is perfect or that he hasn't made mistakes. Saying, though, that this is the Sheriff's jurisdiction and the FBI is here to assist Pima County in NG's case, and the Sheriff's reasons for using the FLA lab are fine. While trying to make the Sheriff look bad, this FBI agent is also making himself and the FBI look bad. JMHO