Maine’s Democratic House speaker says she won’t convene a committee to investigate whether the House chairman of the taxation committee violated ethics rules for working for a ballot referendum campaign.

Republican Rep. Heather Sirocki asked House Speaker Sara Gideon to convene the House ethics committee to consider whether Democratic Rep. Ryan Tipping of Orono has a conflict of interest for accepting at least $9,000 from a group that successfully pushed for a new income surtax to fund public schools.

Gideon told Sirocki in a letter Friday she’s confident Tipping will continue to serve as a fair committee chairman. Sirocki, of Scarborough, works in the dental field and Gideon said Sirocki had introduced related bills.

Sirocki didn’t immediately comment Friday.

A state ethics commission cleared Tipping’s employment. Republicans wanted legislators to review his conduct.

Republican Gov. Paul LePage called on Tipping to resign.