Dennis Kozlowski was very protective of his reputation for personal and business integrity. The driving force behind Tyco, he bristled if anyone raised questions about his company's financial results.

Two years ago, when Tyco's accounting was first queried, Kozlowski attended a dinner party where he encountered Henry Silverman, chief executive of Cendant, the New York real-estate company whose stock had plummeted because of fraudulent book-keeping.

Did it not really annoy him to hear Cendant and Tyco mentioned in the same sentence, asked Silverman. "Henry, it drives me nuts," replied Kozlowski, according to an account of the event in Forbes magazine.

The probe went nowhere and the Tyco chief continued to bask in the exaggerated adulation that is accorded successful businessmen at public functions in the United States.

In April he was invited to speak as a "leader of conscience" at New Hampshire's Franklin Pierce College and last month he lectured graduation students at New Hampshire's Saint Anselm College on how their morals would be tested every day in the big world.

"Think carefully," he advised them, "and for your sake, do the right thing, not the easy thing."

Last week he was to co-chair a fund-raising dinner for the New York Botanical Garden but didn't turn up. Kozlowski had apparently not done "the right thing".

The 55-year-old corporate icon had been forced to resign as Tyco chief executive after being charged with evading more than $1 million (€1.06 million) in sales tax on $13 million worth of artwork, including Fleurs et Fruits by Renoir and Pres Monte Carlo by Monet, that he bought to hang in his 13-room duplex overlooking Manhattan's Central Park.

Because of this the directors had dumped him during a turbulent conference call, which reportedly degenerated into a shouting match and went on until 3 a.m.

Kozlowski is pleading "not guilty". But one of the US's most-hyped business careers has come to an abrupt end. The son of a New Jersey policeman, Dennis Kozlowski helped pay his way through university by playing guitar for a band that performed at weddings.

In 1975, he joined Tyco, a New Hampshire company with sales of less than $20 million a year. After becoming chief executive in 1992, he built it up into a conglomerate of companies providing everything from fire alarms and undersea fibre-optic cables to coat hangers, medical supplies and financial services.

Kozlowski earned the nick-name of "Deal-a-Month Dennis" as he made hundreds of acquisitions, expanding the workforce from 23,000 to a quarter of a million.

His trick was to cut jobs and costs at the companies he snapped up and to pressurise managers to grow at 15 per cent a year - or else. He boasted that he would make Tyco the next General Electric, and BusinessWeek featured him as the "Most aggressive CEO". Investors loved him, especially the trust funds.

Throughout the 1990s Tyco stocks performed so spectacularly that $1 million invested in 1992 was worth $15 million by 1999. Kozlowski acquired luxury homes in New Hampshire, New York, Nantucket and Florida.

HE rode around on Harley-Davidsons and last year skippered his racing yacht Endeavour at the America's Cup Jubilee regatta off the English coast. Money was no object.

However, Kozlowski's "compensation" - chief executive-speak for pay - soared as the share price began falling, and a lot of people didn't like that.

He received $100 million in cash and stock over the past three years, during which time he sold more than $300 million in shares back to the firm. Now it seems even that wasn't enough. Investigators are checking if the company paid for his homes and possessions at a time when the share price was falling over fears that Tyco had used Enron-type accounting to overstate growth and profits.

Company sources have confirmed that Tyco paid for the Fifth Avenue apartment.

The company is $27 million in debt and the stock is down 80 per cent this year, a disaster for the big money managers. Kozlowski joins a growing number of revered chief executives who have fallen from their pedestals, like Kenneth Lay of Enron and Jack Welch of GE - albeit for a personal affair - and Tyco joins a parade of acquisitive companies that lived for the deal, like WorldCom, Cisco and Vivendi Universal, and have seen their stock prices plummet. A survey by Thompson Financial for the Wall Street Journal shows the stocks of the top 50 "acquirers" in the late 1990s have fallen three times as much as the Dow Jones Industrial Average.

Acquiring things by cutting corners, whether a company or a work by Monet, is a risky business it seems.

Unless he beats the rap, it will be some time before Kozlowski is hosted again, as he was at Franklin College just a few weeks ago, as "someone students should emulate".