Washington (CNN) The author of a book alleging some Clinton Foundation donors received favorable treatment while Hillary Clinton was secretary of state said Sunday that he did not have "direct evidence" of any impropriety, but argued the "pattern of behavior" required an investigation into Clinton's record.
Peter Schweizer claims in his forthcoming book, "Clinton Cash," that contributors to Clinton's family foundation had undue influence on American foreign policy. But when pressed by ABC "This Week" host George Stephanopoulos, Schweizer said the record is only suggestive, not definitive.
"The smoking gun is in the pattern of behavior," Schweizer said, comparing his findings to previous research he did on insider trading. "Most people that engage in criminal insider trading don't send an email and say, 'I've got inside information -- buy this stock.' "
Even though Schweizer admitted he had no hard proof of any quid-pro-quos, he did raise several instances in which he said Clinton foundation supporters benefited from State Department actions. And the author noted that several media outlets have begun to follow up on his reporting by dispatching their own investigative reporters to confirm and expand on his findings.
The Clinton Foundation admitted in a blog post on its website on Sunday that it had made "mistakes" as the organization grew but defended its work as transparent and above board.
Schweizer said his role was merely to lay the groundwork for a broader probe by authorities.
"It's not up to an author to prove crime," he said.
Schweizer is also currently reporting on potential ethics violations by Jeb Bush, the former Florida governor likely to seek the Republican nomination.