In June 2012 Elections Canada was investigating Del Mastro for overspending during the 2008 elections. The investigation surrounds a payment of $21,000 made by a personal cheque to Ottawa-based polling firm Hollinshed Research Group for which Del Mastro was not reimbursed, exceeding his personal spending limit of $5,000. Del Mastro has insisted he has not broken any election law and claimed that the $21,000 cheque was for a riding-mapping software called GeoVote that Holienshed intended to launch, and not for telephone calls to constituents during the campaign.