The FSA has been criticised for multiple failures related to its delivery of enforcement documents, including leaving unencrypted discs with a neighbour of the subject of an investigation.
The Complaints Commissioner received a complaint in relation to events which occurred at the end of August 2010.
He outlined the complaint: "You are unhappy that a courier, sent by the FSA, delivered a package to your neighbour (rather than you) between 10pm and 10.30pm at night.
"Specifically you feel that the delivery of a package at that time of night is unacceptable particularly as the package, containing sensitive confidential material relating to an ongoing Enforcement investigation, was simply left with your neighbour."
Outlining his opinions and recommendations, the commissioner, Sir Anthony Holland, criticises the FSA for leaving documents at the neighbour's house, a situation exacerbated by the fact they were not encrypted.
As in a previous case, the commissioner was also critical of the FSA's decision to send a package so late, suggesting a deadline of 8pm would be more appropriate
He says: "I am concerned that the FSA allowed documents to be left with a neighbour with no guarantee that the documents would be passed to you the next morning or indeed in a timely fashion."
In its response to the commissioner's comments, the FSA accepts leaving unencrypted data with the neighbour was an error.
It says: "It is, and was at the relevant time, the FSA's policy for disks containing sensitive material that are sent externally to be encrypted.
"Although no harm resulted, the FSA regrets that the policy was not followed in this instance."
However, it has once again insisted 9pm would be an acceptable deadline for delivering documents without any warnings.
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