The Earthquake Commission has laid a complaint with the police against the man who was wrongly sent an email containing details of more than 80,000 claims.
The commission says Bryan Staples told it on Wednesday he will retrieve the email and use the information, in a dispute over paying some accounts
It says Mr Staples has gone back on his word as he signed a statutory declaration to destroy the email, which he received on Friday.
EQC chief executive Ian Simpson says Mr Staples' email advised the commission that if it paid certain accounts in full within the required timeframe, there would be no media announcement and the matter would die a natural death.
Mr Simpson says the invoices he wants payment for relate to work he began without EQC's prior approval.
Christchurch police say they are assessing the commission's complaint.
Mr Staples is based in Christchurch.