At 10 a.m. today, in the austere confines of a U.S. courtroom here, attorneys are scheduled to begin the delicate process of selecting 12 citizens of Washington who will decide whether Robert H. Campbell, a former judge of the D.C. Superior Court, traded his judicial influence for gifts and cash from a local construction firm.

In what is believed to be the first case of alleged judicial corruption ever brought in this city, a federal grand jury charged in an indictment last August that Campbell, 57, accepted close to $20,000 in cash and gifts, ranging from topsoil to liquor, from the Maryland-based construction firm, in exchange for his dismissing hundreds of thousands of dollars in traffic tickets for overweight trucks issued against firm employes.

The 20-page indictment, the culmination of a federal investigation that began in March 1978, formally accused Judge Campbell, Excavation Construction Inc., and its general manager, bribery and racketerring. The trial, which is expected to last at least three weeks, will be held before U.S. District Court Judge Thomas A. Flannery.

Both Robert Compbell and Larry Campbell (no relation to the judge) as well as the construction firm, have pleaded innocent to the felony charges CAMPBELL, From C1> -- which carry total maximum penalties of 40 years in jail and $50,000 in fines -- and demanded a speedy trial. Unlike the situation in most so-called white-collar criminal cases, which often are repeatedly delayed, this trial begins today on schedule.

According to court records, the former judge, who is expected to take the witness stand in his own defense, strenuously opposed any moves by the government to delay the trial. Campbell, who left the Superior Court bench for health reasons in December 1978, has lost sight in one eye as a direct consequence of problems related to diabetes aggravated by "the nervous stress of this case," Campbell's lawyer, R. Kenneth Mundy, told the court.

The case has "drastically fragmented" Campbell's family, Mundy said, according to the record. Campbell hopes to bring his family together by Christmas, and, if the case is disposed of by then, he hopes to look for a job, Mundy said according to the record. He added that Campbell had been "able to do nothing but sit and vegetate" since the charges were brought against him.

"Until this cloud is removed from his head, he doesn't feel he could step out and do anything. And his health continues . . . to deteriorate," Mundy told Judge Flannery.

Both Larry Campbell and Excavation Construction also resisted any delays in bringing the charges to trial but for different reasons from those of Judge Campbell, according to court records. Arnold M. Weiner, who represents Larry Campbell along with attorney Gerard P. Martin, told Flannery that the business firm wanted the charges in Washington resolved before government posecutors in Baltimore moved forward on a long-standing tax investigation involving the firm.

According to the record, Weiner, perhaps best known as former Maryland Gov. Marvin Mandel's defense lawyer, told Fleannery that he was concerned that publicity in the Baltimore case might adversely affect Larry Campbell. Subsequently, prosecutors in Baltimore have agreed to postpone action in their case until the Washington Trial is completed. Assistant U.S. Attorneys John P. Hume and Carol E. Bruce are prosecuting the case for the government here.

The firm itself, which is represented by Washington attorneys Jacob A. Stein and Robert F. Muse, began reorganization under federal bankruptcy laws in September 1979. At the time, officials blamed financial troubles on "suspicions" aroused by various federal investigations that involved the construction firm.

The grand jury indictment portrayed a 12-year pattern of alleged give-and-take between Judge Campbell and Excavation Construction, a pattern that allegedly began in 1966 when Campbell was staff attorney in the law enforcement division of the D.C. Corporation Counsel's office. Campbell became chief of the law enforcement division of the city prosecutor's office in 1968.

That section of the Corporation Counsel's office virtually had complete authority over Superior Court cases involving traffic tickets, from parking violations to drunk driving. And it waa never a secret in the Superior Court that a driver could plead his innocence -- or offer his excuses -- to the corporation counsel's office and get a case dropped before it ever got to a courtroom.

Campbell, a Republican, was appointed to the Superior Court bench in 1972 by then-President Nixon. Campbell was part of a class of new judges named just after the local court was reorganized and enlarged from a small police court to a court with broad jurisidction over civil and criminal cases brought in Washington.

Campbell himself estimates that he spent up to 22 months as the presiding judge in traffic court during the five-year period he was on the bench.