Kilpatrick, the mother of ousted Detroit Mayor Kwame Kilpatrick, defended her actions in a letter to the Detroit News and said the House Ethics Committee had approved the trip. "The organizing foundation submitted the required information to the Committee on Standards of Official Conduct," she said.
The committee launched an investigation Thursday into whether Kilpatrick and other lawmakers violated House rules by taking the trip last November.
The panel created a subcommittee for a "full and complete inquiry" into charges by the National Legal and Policy Center that the trip to St. Maarten violated House ethics rules because corporate sponsors helped to pay for it.
The watchdog group's president, Peter Flaherty, attended the Nov. 6-9 conference organized by the Carib News Foundation, a self-described educational group on Caribbean-related issues.
Flaherty presented photographs he says he took at the conference that show logos of such sponsors as Citigroup, Verizon, AT&T, IBM and Pfizer.
"There were corporate sponsors' logos on the podium and on the walls. That's against House ethics rules," Flaherty said.