With the financial system on the verge of collapse in late 2008, a group of troubled banks doled out more than $2 billion in bonuses and other payments to their highest earners. Now, the federal authority on banker pay says that nearly 80 percent of that sum was unmerited.

In a report to be released on Friday, Kenneth R. Feinberg, the Obama administration’s special master for executive compensation, is expected to name 17 financial companies that made questionable payouts totaling $1.58 billion immediately after accepting billions of dollars of taxpayer aid, according to two government officials with knowledge of his findings who requested anonymity because of the sensitivity of the report.

The group includes Wall Street giants like Goldman Sachs, JPMorgan Chase and the American International Group as well as small lenders like Boston Private Financial Holdings. Mr. Feinberg’s report points to companies that he says paid eye-popping amounts or used haphazard criteria for awarding bonuses, the people with knowledge of his findings said.

Even so, Mr. Feinberg has very limited power to reclaim any money. He can use his status as President Obama’s point man on pay to jawbone the companies into reimbursing the government, but he has no legal authority to claw back excessive payouts.