We did take testimony last week from another top aide familiar with Secretary Clinton’s email and BlackBerry: Ambassador Stephen D. Mull, executive secretary of the State Department from June 2010 to October 2012. It was Mull who suggested that Clinton be issued a State Department BlackBerry, which would protect her identity while still being subject to FOIA requests.In his testimony, Mull said that he doesn’t remember how or when he first learned about the former secretary of state’s use of the BlackBerry. The Daily Caller reported on the deposition under this headline: “State Dept. Official Who Discussed Hillary’s Private Server Now Says He Can’t Remember Anything About It.”“Do you know how you learned [about Clinton’s server]?” Judicial Watch attorney Michael Bekesha asked Mull.“I can’t recall, no,” Mulls responded.“Do you recall when you learned that?” came the follow-up question.“No. I can’t recall,” said Mull.That line of questioning about a series of August 30, 2011, emails also caught the attention of U.S. District Court Judge Emmett Sullivan. Judge Sullivan cited the emails in his Memorandum and Order granting Judicial Watch discovery into the Clinton email matter:"In August 2011 communication difficulties experienced by Secretary Clinton prompted discussion among State Department staff about whether issuing a State Department blackberry might solve the problem . . . Stephen Mull, Executive Secretary of the State Department at the time, noted that if Secretary Clinton used a State issued BlackBerry, her identity 'would be secret' but that the state.gov email account 'would be subject to FOIA requests.' Ms. Abedin responded 'let's discuss the state BlackBerry, doesn't make a whole lot of sense.'"You may not be shocked to learn that Amb. Mull said he did not recall the circumstances behind the August 2011 email exchange.Amb. Mull now serves as the State Department’s lead coordinator for Iran nuclear implementation.We had yet another deposition this past Wednesday. Our attorneys deposed Karin Lang, director of executive secretariat staff and designated representative for the State Department. Lang was designated by the State Department as its 30(b)(6) witness.A 30(b)(6) witness is assigned to provide the agency’s testimony on the Clinton email issue.Lang testified that key State Department federal recordkeeping officials did not know that Clinton and her top aide Huma Abedin were using non-state.gov email to conduct government business.She also testified that the State Department could not say whether Clinton or Abedin has turned over all emails in their possession that may be potentially responsive to Judicial Watch’s Freedom of the Information Act (FOIA) request.Lang also said that it would not be reasonable to search all 70,000 State Department email accounts in order to retrieve Clinton’s emails. (Clinton has suggested that the State Department would have many of her emails because she sent most of them to State Department employees on their government accounts.)Lang also testified that aof Mrs. Clinton using a Blackberry spurred a State official to ask again if she was using non-state.gov account. Again, he was told “no.” Lang signed, under the penalty of perjury, State Department answers to Judicial Watch’s written interrogatories about the Clinton email system and FOIA.The State Department acknowledged in its answers that it “has no method of identifying which State Department officials and employees had and/or used an account on clintonemail.com to conduct official government business.”Amb. Mull and Ms. Lang are among seven depositions of former Clinton top aides and State Department officials that Judicial Watch has scheduled over the next three weeks.Huma Abedin is scheduled to testify on June 28, and top State Department official Patrick Kennedy on June 29.And we hope the Court will allow us to bring Mr. Pagliano, the Clinton supposed go-to IT expert on her email system, soon (see story above).Our investigation into the Clinton emails is receiving national media attention almost daily. See my most recent interview on The Wall Street Journal’sAnd be sure to watch the Fox News Channel this evening for my interview on the O’Reilly Factor in the 8 pm ET hour.