When he started work as the Whitewater independent counsel in August 1994, Kenneth Starr knew exactly what he did not want to be: a seemingly permanent prosecutor whose investigation dragged on interminably - in short, a Lawrence Walsh, whose Iran-Contra inquiry lasted two administrations past the one he was charged with probing.

Yet 3 1/2 years later, Starr finds himself at the helm of an investigation that has assumed Walsh-like proportions, spending more than $26 million in an inquiry that began as an examination of a 1978 Arkansas land deal and has since ballooned to encompass the firing of White House travel office employees, the gathering of FBI files on Republican White House aides, the possible perjury of President Clinton's former White House counsel and the mysterious reappearance in the White House of Rose Law Firm billing records two years after they were subpoenaed.

Now, with the latest and most explosive expansion of his inquiry - into allegations that the president tried to cover up an affair with a White House intern - the Clinton administration is engaged in an extraordinary public feud with Starr that has underscored two starkly different views of the 51-year-old former federal appeals court judge.

Is Starr, as the White House and its allies charge, an overzealous and politically-motivated prosecutor relentlessly "scratching for dirt", as the first lady, Hillary Rodham Clinton, put it this week? Or is he, as his associates describe him, a reluctant investigator who would like nothing better than to rid himself of the whole affair but is forced to head off in new directions because of White House obstructionism and new evidence of questionable behaviour?

The truth is elusive because so much of the work of Starr's office has been conducted under the necessary veil of grand jury secrecy. But it may well lie somewhere between these views, the story of a miscast man - a political partisan with no prosecutorial experience - in a job that would be difficult under any circumstances but has been made even more so by forces both within and outside his control.

The independent counsel statute creates a unique and powerful creature, unhindered by normal considerations of money or efficiency. His budget is unlimited, his ability to use time and staff unmatched, his success to be judged only on whether he can reel in a big fish.

However, some Justice Department officials who have dealt with Starr over the years do not regard him as overzealous or even unusually aggressive in the way he has pursued his mandate.

"Starr really has not done anything to abuse the kind of latitude that the system grants him," a Justice Department official said. Rather than rapaciously seeking to expand his mandate, said another official, "we are talking about a guy who wanted to hang it up and move to Malibu, after all", referring to Starr's aborted career switch to the deanship of Pepperdine University's law school in California.

While the investigation of the Clintons continues, Starr's team can point to several major convictions - of the former Arkansas governor, Jim Guy Tucker, the Clintons' former Whitewater business partners, James and Susan McDougal, and the former associate attorney general, Webster Hubbell. He has also secured 10 guilty pleas from lesser banking figures in Arkansas.

But Starr's conduct before and after taking the independent counsel job - his alliances with conservative groups, his public comments, his continuation of a legal practice that earns him more than $1 million annually even as he investigates the president - has provided ample ammunition for those who seek to portray him as a Captain Ahab, obsessed with harpooning the great white whale no matter how lengthy the quest.

Yet the Clinton White House in many ways has been its own worst enemy in the investigation, and those who know Starr paint the picture of a man who set out determined to conduct a fair-minded and prompt inquiry only to become increasingly convinced that he was not being dealt with honestly, including by the president and first lady themselves.

It is the White House's conduct - the firing of the White House travel office employees, the gathering of FBI files on Republicans - that has given rise to the expansion of Starr's mandate, some of which has come not at his own but at the request of the Attorney General, Janet Reno.

The story of Starr and his investigation is replete with ironies, the first being the fact that he was put into his position, or so the appointing authorities said at the time, precisely to avoid the very questions of partisanship and unfair dealing now being hurled at him.

The original Whitewater special prosecutor was Robert Fiske, a moderate Republican selected by Reno in January 1994. Eight months later, with the law renewed and Fiske under fire from conservatives for being insufficiently aggressive in pursuit of the president, the three-judge panel in charge of appointing independent counsels abruptly replaced him with Starr. The outcry from some quarters of the Clinton camp was immediate. Starr had been a top aide in the Reagan Justice Department and returned to the department as solicitor general under Bush. He had toyed with running for the Senate and had served on the finance committee for a Republican congressional candidate.

Starr had also spoken out publicly in the Paula Jones sexual harassment lawsuit, disputing Clinton's assertion that he should be immune from being sued while in office - "one of several factors that should have led the court to choose somebody else as a matter of judgment", according to a legal ethics professor, Stephen Gillers.

That "unimmaculate conception", as one Starr associate called it, was bad enough. But his conduct afterwards stoked the fire. He continued his lucrative legal practice as a partner at Kirkland & Ellis, earning $1.1 million in 1996, the last year for which he has filed a financial disclosure form.

He argued for the Brown & Williamson tobacco company in an appeals court case involving class-action lawsuits, drawing criticism that he was aligning himself with an industry that was spending millions to oppose Clinton and the Democratic Party. Even his own in-house ethics counsel told the New Yorker in 1996 that "what he's doing is proper . . . but it does have an odour to it".

One person who knows him well says: "Ken is the kind of person who is so confident of his integrity that he can't imagine anybody would want to apply conflict of interest rules to him."

As he has tried to get to the bottom of the original Whitewater allegations - including whether Clinton, while governor of Arkansas, pressurised a businessman, David Hale, into making an illegal loan to a Whitewater business partner, Susan McDougal - two critical witnesses have remained unavailable: the former Arkansas governor, Tucker, and McDougal herself.

McDougal, one of the partners with the Clintons in the Whitewater investment, has been jailed for contempt for 17 months for refusing to testify despite a grant of immunity.

Then, in January 1996, the Rose Law Firm billing records - related to work that Hillary Clinton did for the McDougals' Madison Guaranty Savings & Loan - were discovered in a private area of the White House, opening up a whole new avenue of investigation. That inquiry, too, was stalled for a time with litigation that began in August 1996 over whether notes by White House lawyers of their meetings with Hillary Clinton were shielded by privilege.

As the investigation has gone on, Starr has been accused of playing hardball and using improper tactics. Last summer, the Washington Post reported that FBI agents and prosecutors working for Starr had questioned Arkansas state troopers about their knowledge of any extramarital relationships Clinton may have had as governor, as well as a number of women whose names had been mentioned in connection with him.

Clinton's lawyer said it showed that Starr's investigation was "out of control", but Starr said he was using "well-accepted law enforcement methods" to get relevant information about the land deal and any efforts by administration officials to obstruct his inquiry.

Some lawyers who have dealt with Starr have complained that he has repeatedly called the same witnesses before the grand jury on peripheral matters in order to create a "perjury trap", issued overbroad subpoenas, and pursued the littlest of fish in his zeal to get at higher-ups.

"They had an attitude of intimidation and nastiness that maybe you treat the Mafia and paid Mafia lawyers that way," said one lawyer who has had extensive dealings with the office.

Others reported professional dealings. "I had no problems with them," said Stanley M. Brand, who represented a former Clinton adviser, George Stephanopoulos. "They were . . . guys who seemed to me to be well within the pale of what I'm used to dealing with."

Now, with an entirely new line of inquiry before him, Starr's hopes of moving on to Pepperdine law school - an idea he raised last February but quickly abandoned after a public outcry - appear dimmer and dimmer.