J. Walter Jones, an Annapolis banker who was one of former Vice President Spiro T. Agnew's closet friends and most active political fund raisers, pleaded guilty today to soliciting an illegal $10,000 contribution to the 1972 Republican presidential campaign.

Federal prosecutors also charged today that Jones received cash payments from a Washington area architect in exchange for using his influence to obtain architectural contracts from the federal General Services Administration. Prosecutors said that Jones received 5 per cent of the awarded contract price from the unnamed architect. Jones' attorney denied the charges.

Jones' guilty plea brings to a close a series of criminal cases that began two years ago with the indictment of Jones and three others in connection with the illegal $10,000 contribution.

Prosecutors had alleged that Jones obtained the contribution from the Singer Company after assuring its officers that the company would benefit from favorable treatment in the handling of federal contracts on the part of the Nixon administration.

The four men - as well as the Singer Company - were indicted in March 1975. The 56-year-old Jones was described in court by federal prosecutors as the "bagman" who helped Agnew collect kickbacks from architects and engineers in Maryland.

The Singer Company and two of the three men charged, John W. Steffey, treasurer of the Maryland state finance committee for the Committee for the Re-election of the President, and James Fanseen, a Baltimore lawyer who acted as a go-between in the scheme, pleaded no contest in the case a few weeks after the original indictment. Charges against the fourth man, Raymond A. Long, a Singer executive, were subsequently dismissed.

The Singer company, famous for its sewing machines has been a major contractor with the General Services Administration because its Simulation Products Division manufacturers sophisticated electronics gear that simulates the handling of ships and aircraft.

According to the prosecution's statement of the case, which was given to U. S. District Judge R. Dorsey Watkins today after Jones had entered his guilty plea, Jones, then chairman for the Maryland Finance Committee for the Nixon-Agnew ticket, solicited the illegal contribution from Fanseen, the attorney and go-between in the scheme.

"Jones then proceeded to tell Fanseen that Singer, by giving a contribution, would ensure help for itself in the securing of future government contracts," Assistant U.S. Attorney Daniel Hurson told Judge Watkins.

"Jones indicated that he was aware that Singer has been having trouble with government contracts and that, therefore a substantial contribution wouldn't hurt them." Hurson said.

According to Hurson's summary. Fanseen then spoke with Arthur (Bud) Carter, general manager of the Simulations Products Division, about the Jones proposal. "Fanseen made it clear to Carter that because of Jones' close relationship with Vice President Agnew, when they spoke to Jones, they were speaking to Agnew," Hurson said.

Hurson said that a luncheon was then arranged at the Capitol Hill Club in Washington for Carter. Jones, Fanseen, campaign finance official Steffey and Martin A. Leader, another Singer executive. After the Singer representatives indicated their willingness to make a contribution. Jones suggested they launder the money by using "consultant method," Hurson said.

"The Singer Company would make a check payable to a bogus consultant, who would deposit it as income and pay taxes on it. After those taxes were substracted, the money would be transmitted" to the campaign, hurson said.

"Jones assured those present that this would be perfectly safe," Hurson said, "because taxes would be paid and that was the only area of legal concern anyone would have."

Carter and Leader were subsequently indicted for conspiracy in connection with the contribution and were fined $500 and $250 respectively for their part in laundering the Singer money.

Jones' attorney Plato Cacheris, objected to portions of the Hurson summary, calling them "embellishments (and) Skoinikisms" in a reference to Assistant U.S. Attorney Barnet D. Skoinik, who prosecuted the Agnew-related cases.

But Cacheris also told Judge Watkins, "There's no question that the contribution was made by Singer and Mr! Jones has a part in it." At the time of the indictment Cacheris charged that his client was the victim of a "two-year vendetta" by the U.S. Attorney's Office. Jones initially pleaded innocent to all nine counts of the indictment.

The prosecutors did not identify the architect who allegedly received federal General Services contracts through Jones.

The prosecutors' statement of facts said that "a total of almost $12,000 was paid" top jones between 1969 and 1972 by the unidentified architect "in consideration for some six to eight" contracts in the 30,000 to $50,000 price range. "Jones always assured this man that the money was being channeled to Republican campaign coffers," prosecutors said.

"Jones was able periodically to give the architect precise 'inside' information concerning" contracts and "the budgeted price which GSA was in a position to pay for each job."

"Thus, the architect knew precisely what price proposal by him would be likely to win the award of the job," the prosecutors alleged.

"Jones also periodically told the architect that he would soon be meeting with Arthur Sampson, then head of GSA, and that he would request more work for the architect. Shortly after such meetings between Jones and Sampson, the architect would get a call from GSA inviting him to come in and discuss additional work." Sampson was removed as head of GSA during the Ford administration.

Prosecutors also charged that Jones sold tickets to a fund raiser for Spiro T. Agnew in exchange for "getting certain housing projects pushed through the bureaucracy of the Department of Housing and Urban Development."

According to Hurson's presentation, after the Singer executives agreed to launder the money through a phony consultant, Jones told Fanseen that Baltimore engineer Lester Matz - one of the chief witnesses in the 1973 kickbacks investigation which led to Agnew's resignation - would take a payment from Singer and pay in cash to the campaign committee what was left after taxes.

As a result, $15,000 was paid to Matz who then turned over $10,000 to Jones' chauffeur, Hurson said. Jones faced a maximum sentence of five years in prison and a $5,000 fine for the offense, a felony.