His father was a parole officer and a college football legend, his mother a school principal. His grandfather was a circuit-riding Baptist preacher and he, not surprisingly, has assumed a little authority himself.

D.C. Auditor Otis H. Troupe has become the pencil-toting nemesis of Mayor Marion Barry's administration. In a city government dominated by the powerful mayor, the auditor provides a forceful counterweight to the executive branch.

Troupe, who was underestimated by some when he took over from the much-admired auditor Matthew S. Watson in April 1981, has stung the Barry administration with audit reports criticizing poor management at the troubled Bates Street housing redevelopment project, "cronyism" at the D.C. Lottery Board and the District government's practice of rewarding former city officials with consulting contracts.

The enigmatic Troupe, a hulking figure who keeps to himself but counts among his political connections his aunt, Marjorie Parker, a former chairman of the board of the University of the District of Columbia, finally drew fire from Barry a week ago when the mayor attacked Troupe's role in the controversy that has enveloped UDC this summer.

Barry, his aides and high UDC officials portrayed Troupe, a City Council chairman appointee who orbits outside the mayor's sphere of influence, as a biased crusader whose audits of UDC accounts turned into a vendetta against Robert L. Green, who was forced to resign recently as president of the university. Barry administration officials also expressed concern that Troupe may have a campaign of harassment under way against the executive branch.

"He seems to have the psychology of a prosecutor," said Herbert O. Reid, a UDC trustee and the mayor's legal counsel. " . . . If he is running for council chair or mayor, he ought to get out there and run."

Supporters of Troupe offer another picture -- of an independent civil servant and a loner free of political associations.

"His job is his passion," said one council staff member. "He is the city auditor and that is all anybody has on him."

City Council member John A. Wilson (D-Ward 2) described Troupe as "one of the better public servants in the city government."

"Any time you carry out that function well, without discrimination or malice, and objectively, people are not going to be too happy with you," Wilson said. "If you do what they tell you to do and avoid things they tell you to avoid, then they are happy."

To say Troupe occupies a corner office of the second floor at 415 12th St. NW, is to sidestep the issue. Troupe anchors the building.

A former football defensive guard with a wide frame and bone-crunching grip, the 40-year-old auditor likes to project a no-nonsense image as the man responsible for monitoring the ornate District Building, which lies just in sight of Troupe's office across Pennsylvania Avenue.

"Here's your profile," he said. "Otis Troupe gets to work at 8:30 or 8:40 in the morning and he's available to council members. He audits the city. He goes home. He's not a member of this club or that club or this clique or this group or any of that bull . . . . "

Troupe presides over an office of 15 auditors and aides who review District government programs, management, finances and legislation -- a function similar to that of the District's inspector general, except that the inspector general serves at the pleasure of the mayor and is not obligated to make reports public.

Troupe's term ends March 31, 1987, six years after he was appointed by then-City Council Chairman Arrington L. Dixon. The second man to serve as auditor, Troupe was selected for the job because of his professional credentials and distinguished lineage, according to Dixon.

Troupe's aunt, Marjorie Parker, who was appointed by former president Richard Nixon to the old appointed City Council, is married to U.S. District Judge Barrington D. Parker. His grandfather, the Rev. John L.S. Holloman, was a North Carolina circuit rider who came to Washington in 1917 and was pastor of the Second Baptist Church here for 53 years.

Troupe's mother, Carolyn, is a retired school principal and his father, Otis E. Troupe, is a New Jersey native who was a record-breaking fullback at Morgan State University in Baltimore in the early 1930s before moving to Washington to work as a Howard University coach and then as a D.C. parole officer.

An only child and unmarried, Troupe is described by his mother as "somewhat reclusive" and serious-minded, the kind of man who takes Elizabeth Drew's political writings to read on beach vacations, which are rare.

Troupe was student body president at McKinley High School in 1962, then left the city in search of higher education and employment. Eighteen years later, he came back with an impressive resume: a bachelor's degree in English from Yale University; a law degree from Boston College; a masters in business administration from Columbia University; jobs as a market analyst for Exxon International in New York and as director of economic development for the Bedford Stuyvesant Restoration Corp.

In Washington, he took posts as budget analyst for the City Council and as a community development specialist for the U.S. Comptroller of the Currency before becoming auditor.

Yet it is a measure of the controversy Troupe has stirred up that even as Dixon describes him as "impeccable professionally," attorney Vincent H. Cohen labels him "clearly not a professional."

"Otis Troupe," said Cohen, who was hired by the UDC Board of Trustees to assist in handling the Green controversy, "cost the District of Columbia government several thousand dollars because the board had to go and hire an independent auditor to get what they felt was an unbiased look at the situation because of the nature of Troupe calling people crooks."

In the middle of the controversy over Green's expenditures of university funds, the trustees engaged the national accounting firm of Coopers & Lybrand to examine the same books Troupe had audited. Their rationale, according to Cohen and officials in the Barry admnistration, was that Troupe was not objective. The auditor, said Cohen, had told several individuals that he believed the UDC president was a "crook."

"Bob Green never had a chance," said Cohen. "Because if the auditor prejudged him a crook, you've got an auditor and a self-fulfilling prophesy."

Troupe, who denied ever making such a statement, said he viewed the attacks on him as a campaign by sore losers.

"I know that the mayor gets very nasty when he loses," he said. "The whole Green thing was a personal tragedy to him because of the depth of his involvement in bringing him Green here and propping him up even as the evidence mounted and mounted."

The Coopers & Lybrand audit, which is continuing, has sustained some of Troupe's findings but has differed in some of its conclusions about expenditures by Green.

Troupe first came under fire this summer after he alleged in audit reports that Green had misspent thousands of dollars of UDC funds for consulting fees, travel, catering and household items.

Troupe had begun the inquiry earlier this year at the request of Council member Hilda Mason (Statehood-At Large), chairman of the education committee that has oversight responsibility for UDC.

When elements of Troupe's draft audits were reported by The Washington Post and The Washington Times, UDC and government officials began crying foul. Council Chairman David A. Clarke, reacting to a Troupe quote in the May 3 Washington Post, wrote the auditor a letter saying, "To indicate in the press that something may be amiss when later you may find that it was not, does not serve the public well. I would appreciate an explanation on this matter."

Barry, in a news conference two days before Green's resignation Aug. 23, criticized "auditors who leak draft reports" and complained that Troupe had assumed an adversarial posture in the case. Further, the mayor said he didn't think Troupe would be inclined to audit UDC's books going back to 1981 and 1982 when Troupe's aunt was board chairman.

Troupe did audit the UDC athletic department in 1982, however, and faulted it for its handling of more than $105,000 in grant-in-aid tuition payments for athletes.

Responding to Barry's news conference remarks, Troupe denied leaking information and observed that the draft reports had been distributed to UDC officials before they ended up in print. Referring to one personnel document that was leaked to the press, Troupe asked, "Why would I leak my Exhibit A that was going to go public in seven or eight days anyway?"

City Administrator Thomas Downs said the hostility between the auditor, an arm of the legislative branch, and the executive branch results in part because the separation of powers under the decade-old home rule charter is not yet clear.

"Because this is a new government," Downs said, "the delineation of roles and responses is an ongoing process. The executive branch will sometimes disagree with the legislative arm over powers and roles and responses."

Troupe sees the conflict less in abstract terms than as part of his mandate to investigate any operation of the city government. He has made it clear his office will continue to keep a spotlight on the administration to uncover irregularities. A major concern is the city's purchasing practices.

"In too many instances, it is much too easy to award negotiated services contracts -- that is, a contract without competitive bidding," he said. "In too many instances, it is too easy for a single executive . . . to obligate the city to very significant amounts or resources. In too many instances, we spend a huge amount of money and we don't assign guys to monitor the performance on the contract."

Hunched behind a cluttered desk in a plain office, Troupe insisted he keeps personalities out of his work. He recalled a schoolboy's ambition that just might hint of the grown man. "I always wanted to make sure that I was competitive in every aspect," he said. "In football, although I wasn't a superstar, I think I could bump heads with anybody out there."