Most people expect a little trouble in divorce court. But D.C. Superior Court Judge Frank Schwelb, who recently spent several months mediating family splits, says he's so fed up with what he calls the "altogether intolerable" frequency of lying and other deceptions in his courtroom that he has taken action.

In a highly unusual move, Schwelb has asked the U.S. attorney's office to consider prosecuting four persons for perjury or forgery. A criminal investigation is under way, sending a wave of worry through the town's divorce lawyers, many of whom acknowledge that "exaggeration" has become a way of life in many divorce cases.

"The nature and frequency of perjury and like conduct which the court has encountered in its current assignment to Family Motions," Schwelb wrote in a 13-page memorandum to the U.S. attorney's office, "is more extreme than in other assignments and altogether intolerable."

In three of the cases, Schwelb said, one partner allegedly lied about income, employment or child-support payments. In a fourth case, the wife is accused of forging endorsements on checks.

Lawyers for the four call the charges grossly unfair or a misunderstanding of the facts.

"I don't blame Judge Schwelb one bit . . . . All too many people are sloppy or don't think about what they are saying," said Elizabeth Guhring, the lawyer for a man accused of concealing more than $100,000 in income to avoid paying more child support. "But in this case, I think there was some misunderstanding . . . . It is a case of sloppy business records."

According to Schwelb, Albert Nellum of Reston did not include on his financial statement $113,000 he received during a three-year period from the consulting company he owns. When asked to explain the discrepancy between his reported income and his bank deposits, Nellum described the unreported money as loans, although he paid no interest nor made payments on the loans, Schwelb said.

"The court found that the characterization of these payments as loans was a patent sham," said Schwelb.

In his tersely worded memorandum, Schwelb explained that one of the purposes of referring the four cases for prosecution is to warn others that lying, although common, is not acceptable in a court of law.

"Perjury and fabrication pollute the very lifeblood of the judicial system," wrote Schwelb, who said one of the most frequent forms of lying occurs in financial statements. Often, he wrote, a wife submits a list of expenses that far exceeds the income she has had available during the last several months, yet when asked about the discrepancy, she reports only a small deficit.

"Her case would surely collapse at this point," Schwelb said, "but the inconsistencies in the husband's statements are often even more acute."

"Lawyers are talking about" Schwelb's memorandum, said Washington lawyer Robert Liotta, who counseled a client last week to make sure she understood she was preparing a projection of the income she thought she needed, rather than what she was actually spending.

"But, contrary to what Schwelb might think, lawyers automatically discount financial statements ," Liotta said. "It may not be a good system when people automatically don't believe these things, but that is what happens . . . . This may make people more cautious."

In one of the four cases, Schwelb said he suspected a man might be lying about making child-support payments when the man brought in a notebook showing payments that did not match the amount he was scheduled to pay. On one page, Schwelb found, Roy Gaddy wrote he had made payments of $62.50 every two weeks since 1972.

"In fact, the husband was not ordered to pay $62.50 every two weeks until 1974, and had been paying only $35 biweekly before that," Schwelb wrote. Gaddy eventually admitted, "with tears" in his eyes, the judge said, that he had written some of the entries after his wife claimed in court papers that he had not paid child support. Schwelb said Gaddy, however, continued to maintain that he had made the payments and that his documentation was stolen.

Neither Gaddy nor his lawyer could be reached.

In the case involving allegedly forged check endorsements, Schwelb said he referred it for investigation despite the wife's prior admission to forging a name on a cashier's check written by her husband.

The woman, Theresa O. Smith, and her attorney, Donald T. Cheatham, told Schwelb they already had discussed the forged endorsement with the U.S. attorney's office and had been assured that Smith would not be prosecuted. But Schwelb said possible additional forgeries on the wife's part came to light during the divorce hearing.

"It's extremely unfair," said Cheatham. " . . . It's like going in for a traffic ticket and the judge talks about chaining your dog up. 'You didn't chain your dog up, so you must be guilty of speeding.' "