An email sent to Hillary Clinton in 2009 that the State Department recently gave to the watchdog group Judicial Watch appears to not have been included in the records that the former secretary of state turned over to the agency in December 2014.

The March 20, 2009 message is not the first Clinton appears that she appears to have withheld from the State Department. Clinton failed to give the agency 15 emails that she exchanged with her longtime friend Sidney Blumenthal.

But the email, which was included in a batch of records that Judicial Watch released on Thursday, is the first one to be released publicly.

Tom Buffenbarger, the president of the International Association of Machinists and Aerospace Workers (IAM), sent Clinton the email.

The contents appear innocuous. Buffenbarger expressed concern to Clinton over a global manufacturing downturn. It is unclear if Clinton responded to Buffenbarger, who recently endorsed her for president.

It is unclear why the email was contained in the records handed over to Judicial Watch. The documents were provided to the group in response to its lawsuit against the State Department for the emails of Clinton’s then-deputy chief of staff, Huma Abedin. She is not listed as a recipient or sender on the email chain.

The absence of the email on the State Department’s website — which is where the rest of Clinton’s work-related documents have been published — raises the obvious question of what happened to the document. Did Clinton delete it? Did she do so accidentally or on purpose? Did she delete other emails? Or, is there another technical explanation for the inconsistent paper trail?

The Clinton campaign did not respond to a request for clarification.

Judicial Watch’s trove of new emails contains numerous others that Clinton sent and received as secretary of state but did not give the State Department.

But those emails were sent before March 18, 2009, which is the date the Clinton campaign claims she had the earliest access to her old emails.

Clinton’s campaign has given different explanations for the gap, but it has seemed to settle on the claim that Clinton only had access to emails that were housed on her private server, which was not activated until March 18, 2009.

Asked about the email, State Department spokesman John Kirby provided no specifics, but issued a standard statement.

[dcquiz] “Secretary Clinton and her team have indicated that they provided the Department with all work-related emails in her possession from her time at the Department,” he told TheDC, noting that Clinton “has also indicated that she does not have access to work-related emails beyond those she turned over to the Department.”

“In addition, at the Department’s request, Secretary Clinton confirmed for the Court that she believed that all her emails on clintonemail.com in her custody that were potentially federally records were provided to the Department.”

He added that in Sept. 2015 the State Department also asked the FBI to inform them if any additional Clinton emails were recovered. He did not say if the FBI has contacted State in that regard.

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