Green party Leader Elizabeth May had asked the commissioner to examine whether Prime Minister Stephen Harper's actions amount to a conflict of interest.
A similar complaint was filed by accountability group Democracy Watch.
May asked why former Labrador MP Peter Penashue (pen-ASH'-away) was allowed to make a $1.4 million spending announcement in Labrador four days before he resigned over illegal campaign donations.
May also asked whether Harper was advancing Penashue's personal interests by allowing him to run before prosecutors have decided whether to lay charges.
Penashue blamed mistakes made by his former official agent and is running for re-election in a byelection Monday.
Ethics Commissioner Mary Dawson says May's request did not set out reasonable grounds to believe the Conflict of Interest Act was contravened.
She says actions to improve a candidate's election prospects don't necessarily advance private interests.
Dawson also says the fact that Harper and Penashue were cabinet colleagues does not show they were friends as defined under the Act.
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