The ongoing investigation into the disappearance of Nancy Guthrie has hit a snag, as Pima County Sheriff Chris Nanos is reportedly blocking the FBI from accessing key evidence, including a glove and DNA found at her home. This evidence is critical for the FBI's processing at their national crime laboratory, which could potentially provide vital leads in the case. The Sheriff has chosen to send the evidence to a private lab in Florida instead, which has raised concerns among federal officials about the delay and efficiency of the investigation.

Federal law enforcement sources express that this obstruction is not only unnecessary but could further hinder the progress of a case that is increasingly urgent. There are implications of previous setbacks, and the decision to divert the evidence could complicate legal proceedings and impact how swiftly justice can be served if any suspects are identified. The lack of FBI involvement also raises questions regarding the collaboration between local and federal law enforcement during high-stakes investigations.

As the situation unfolds, it highlights the complex dynamic between state and federal agencies in criminal investigations. This case, particularly due to its local importance and the significant public interest it has generated, underscores the critical need for effective cooperation to resolve missing persons cases efficiently. Failure to do so may not only affect this case specifically but could set a concerning precedent for future investigations in similar circumstances.