A leading critic of House Speaker Jim Wright said Tuesday he isn't sure Wright was wrong in using an aide to help write a book, but the speaker's activities should be investigated.

The aide was paid $2,000 from official congressional accounts for expenses during a 1984 trip to Texas to oversee final editing of a privately published book by Wright, House rec-ords show."I'm not sure, frankly, whether we have a problem here or not with this particular case," Rep. Newt Gingrich, R-Ga., said on the CBS show "This Morning."

"There's clearly a legitimate public policy role served in writing books," Gingrich said, "The question would come, whether the primary job of that staffer was to write a book which was being written purely for profit, or whether that was a natural part of his job, doing something that reflected a public policy interest."

"I think every member of Congress has at times used their staff in a legitimate way to look at serious public policy pronouncements or serious efforts to influence public policy," Gingrich said.

But he reiterated previous calls for a House Ethics Committee investigation of Wright's activities.

Rep. Barney Frank, D-Mass., also said Wright should be investigated. Frank said he doesn't consider accusations against Wright valid, but feels that an investigation would help restore public confidence.

The book, "Reflections of a Public Man," published by a longtime Fort Worth friend of the speaker, brought Wright nearly $55,000 in royalties.

Matthew Cossolotto, who has since left Wright's staff, said in a telephone interview Monday that his Texas trip was the culmination of several months of on-and-off work in Wright's Capitol Hill office to help the Texas Democrat draft the book's manuscript.