In this Oct. 18, 2011, image, Hillary Clinton, then secretary of state, checks her BlackBerry from a desk inside a C-17 military plane on her departure from Malta bound for Tripoli, Libya. (Kevin Lamarque/Pool photo via Associated Press)

A State Department official produced to answer questions in a civil lawsuit probing Hillary Clinton’s use of a personal email server said no officials responsible for handling public records requests knew of her private email account while she was secretary, but she was instructed not to answer whether the department’s top legal office knew, according to a transcript released Thursday.

In a deposition Wednesday, answers provided by Karin M. Lang seemed to corroborate several defenses raised by Clinton and her aides in the handling of the controversy while challenging other explanations given in a lawsuit by the conservative group Judicial Watch that examines whether Clinton’s email setup thwarted the Freedom of Information Act (FOIA).

Judicial Watch’s lawsuit concerns a 2013 request for public records information about Clinton aide Huma C. Abedin’s employment arrangement.

Lang, a career employee who in July 2015 became director of the executive secretariat staff, which is responsible for records management, said that while a unit responsible for FOIA requests was told Clinton had no government email account when she took office in January 2009, no one in the unit asked whether she used a personal account to conduct business before she stepped down in 2013.

“Prior to Secretary Kerry, no secretary of state used a state.gov email address,” said Lang, supporting an explanation given by aides to the presumptive Democratic presidential nominee that her email setup at the State Department was not unusual.

Lang said the director of the FOIA unit grew curious about the arrangement “when Mrs. Clinton’s photo appeared in the media with her using, appearing to use some sort of a mobile device.”

By Lang’s account at the deposition, the unit head, Charles Finney, told Lang in a recent debriefing that, at the time the photo appeared, he checked with the secretary’s information technology office, which confirmed that Clinton still did not have a department email account.

Lang said she was not aware of any follow-up and did not know when the conversation took place. She also said that when Finney shared the recollection with her, he could not recall with whom he had originally spoken.

Lang’s sworn deposition statements added context to findings in a sharply critical report by the State Department’s inspector general, who concluded that Clinton’s use of a personal server was “not an appropriate method” for preserving official emails.

Lang, accompanied by four lawyers for the State and Justice departments, was instructed not to answer whether the State Department’s Office of the Legal Adviser was aware of Clinton’s server, or whether the department’s FOIA process or searches in the Judicial Watch case were adequate. Such queries violated attorney-client privilege or were a legal judgment, the lawyers with Lang said in objecting.

Lang said the FOIA office did not begin to search for records in response to Judicial Watch’s 2013 request for information concerning Abedin’s employment until after the group sued and that at the unit chief’s direction, the FOIA office searched only human-resources records, not emails.

After the existence of Clinton’s personal server was reported in March 2015, the search expanded to cover official email accounts used by four senior officials.

Lang said it was only over the summer of 2014 that department officials responsible for record-keeping learned of and began to inquire about the use of personal email accounts for government business. That was when they first noticed such addresses in documents being reviewed, she said.

In her deposition, Lang defended the searches in Judicial Watch’s Abedin request as sufficient. However, she said a statement by Cheryl D. Mills, then Clinton’s chief of staff, in which Mills said she assumed Clinton’s emails would be captured in recipients’ State Department accounts, was impracticable.

“It would not be possible to do that [search for emails from Clinton] except by searching individual . . . by individual, which would not be reasonably possible,” Lang said. “The department has 70,000 employees worldwide.”