Enron Corp. "pushed the envelope" when it allowed 127 of its top executives to take $53 million of some $200 million in deferred compensation just before it filed for bankruptcy protection in late 2001, tax experts told a Senate committee hearing yesterday. And some said it was unclear how widespread such practices are in the corporate world.

"The company permitted its executives to defer staggering amounts of income but took measures to insulate them from the risk of nonpayment that the law requires as a trade-off for tax deferral," Pamela F. Olson, assistant Treasury secretary for tax policy, told the Senate Finance Committee.

She noted that to qualify for deferral, money and other assets put aside for executives are supposed to remain accessible to company creditors.

In other words, there must be some risk that the executive will never collect. Otherwise the executive would have to pay tax on the compensation right away.

Though a certain amount of information about executive compensation appears in companies' filings with the Securities and Exchange Commission, little is available on how extensive these practices are.

But Charles E. Essick, head of the Houston office of compensation consultant Towers Perrin, repeatedly told the panel that his firm had advised Enron based on its extensive collection of information about what other companies are doing.

He said much of Enron's compensation arrangement reflected "standard practices in the marketplace."

His insistence that his firm had never advised Enron to do anything that might be beyond the pale, nor that he saw any evidence that Enron was doing any such things, provoked some skepticism from members.

"It seems that what you're telling the committee, then, is if everybody else that you're surveying out there is doing something that's pushing the envelope and hiding stuff from the IRS, you go to your client and say, you're right, you're right there with 'em," said Sen. John Breaux (D-La.).

Sen. Charles E. Grassley (R-Iowa) said he was bothered by abuses of the executive pay system and will consider legislation to better oversee corporate compensation plans.

Olson and other tax experts said the last time the Internal Revenue Service made a serious effort to tax this kind of pay, Congress passed a law forbidding it and Treasury from writing any new regulations on the subject.

The Bush administration has proposed repealing that legislative ban, and the Joint Tax Committee, which recently published an extensive report on Enron's tax and compensation record, agreed.

But Olson cautioned against trying to do too much through the tax laws because such efforts can have unintended consequences.

She pointed to the current $1 million limit on how much companies can deduct for corporate pay. That allows an exception for stock options, which have exploded in popularity. Critics say they carry with them an incentive for executives to manipulate reported earnings.

"We . . . urge the committee to address the corporate governance and accountability issues raised by executive compensation directly, rather than through the tax code," Olson said.

Charles E. Essick testifies yesterday. With him are law professor Kathryn J. Kennedy and compensation expert Bruce J. McNeil.