In its July 15 response, the mayor's office agreed to produce some logs. It said some of the request was "unduly burdensome," an exemption under Freedom of Information Act law, because it would require workers to produce thousands of emails. And it said it had no texts, which typically are not stored. The mayor's office also said it had no records responsive to the request for emails and texts in which Emanuel conducted city business on personal devices and argued it was not required under the law to produce those.