Alfred Landry filed a report Wednesday with the Speaker that says he doesn't have jurisdiction to investigate because Greg Davis didn't run again in the Sept. 22 provincial election and is no longer a sitting member.
New Democrat Leader Dominic Cardy filed the complaint in March, alleging Davis was in violation of conflict of interest rules by failing to report the $5,125 loan with the clerk of the legislature.
The party loaned the money to Davis after he fell behind in rent for his riding office from February to June 2012.
Landry said he tried to contact Davis in April and May, but got no response.
Cardy said Landry's decision not to investigate raises questions about what the commissioner is able to investigate.
"It does raise some questions around scope of authority and how far back in time you can go," Cardy said. "Also, let's put some more controls in place so that cases like Mr. Davis' can't happen again."
In July, members of the legislative administration committee did make changes, so that rent for constituency offices is now directly paid by the legislative assembly.
Progressive Conservative Opposition Leader Bruce Fitch said he accepts the commissioner's report.
"The commissioner did his job, the report's wound up and the file is closed," he said.
When asked if the commissioner needed broader powers, both Fitch and Liberal Finance Minister Roger Melanson said they need more time to review the report.