Before a dinner last night honoring Clarence Mitchell Jr. and the late George Meany, Mitchell sat on the steps in the middle of the reception room and puzzled over why certain leaders keep saying civil rights gains are on hold. Vernon Jordan said it last week; the U.S. Commission on Civil Rights said it the week before.

"I don't understand those who remain pessimistic," said Mitchell, whose career of pushing for legislative justice stretches back almost 50 years. "This administration has made some solid contributions. The tremendous desegregation of the federal judicial system is the best example."

When President Carter arrived to address the Leadership Conference on Civil Rights' 30th anniversary dinner, Mitchell repeated those sentiments, a love fest gesture that the president mush have loved and few at the dinner argued with.

Explaining that his administration had tried for three years to meet the expectations of civil rights and labor groups. Carter said, "Women, Hispanics, blacks, the poor and elderly still [WORDS ILLEGIBLE] equality in our land. In the [WORD ILLEGIBLE] three years we haven't done much, but we have begun." In his almost conversational tone, Carter borrowed a line from Rep. Parren Michell (D-Md.), the honoree's brother: "We are not going to be satisfied with blacks driving the bus, but we want them to own the bus company."

Along with the 550 people gathered in the Capital Hilton ballroom, Carter watched short films about Meany and Mitchell. Each had a characteristic tone: Menay was up-front, fighting and speaking for "the little people," and Mitchell was taking the modest tack, giving credit for the momentum of the civil rights struggle to another colleague, Roy Wilkins.Carter laughed heartily at each scene of Meany fighting with a president, even one of himself.

Lousi Nunez, the staff director of the Civil Rights Commission, which recently criticized the federal government and Congress for the "drifting" of civil rights gains, left the dinner impressed. "Our report reflected a mixed picture. And the president's appearance and presentation shows his commitment." John Siegler of the Marine Engineers Beneficial Association said, "Clarence Mitchell set the right tone. And Carter has worked for better labor laws, but we have a bad Congress."

There was some disappointment. Sister Marion Montague of Network, a Catholic lobbying group, commented, "It was political. But it was so low-key, I was surprised, given the opportunity he had to make some points before Ted Kennedy's speech tomorrow." Her companion, Sister Anne Margaret Cahill, added, "We were hoping for a new commitment to human rights, a reassurance after his defense announcements this week."

Ronald Brown, a Kennedy strategist, said, "It's clear to me and most in this room that the administration has not kept its promises. Most folks here are disappointed, but they are not saying."

The room has a fair sprinkling of Carter appointees associated with domestic and equal rights battles: Patricia Harris, the Secretary of HEW; Eleanor Holes Norton, head of the Equal Employment opportunities Commission; Ernest Green, assistant secretary of Labor; Stuart Eizenstat, chief of the White House Domestic Council, and Louis Martin, White House special assistant. Also at the dinner were Sens. Daniel Patrick Moynihan (D-N.Y.), Charles Mc C. Mathias, (R-Md.) and Quentin Burdick (D-N.D.), HUD Secretary Moon Landrieu, Rep. Robert Garcia (D-N.Y.) and J. C. Turner, Washington labor leader; Bayard Rustin, civil rights activist, and Eleanor Smeal, president of NOW.

Accepting the award for Meany from Muriel Humphrey, AFLO-CIO president Lane Kirkland said, "the fight for civil rights was not won in George Meany's lifetime, it won't be won in ours, or our children's, because the foes of inequality are as enduring as we are . . . We look not at how far we have come but how far we have to go, and the AFL-CIO has booked full passage." And President Carter smiled in endorsement. On the way out, with a rendition "The Battle Hymn of the Republic" echoing, Edward Brooke, the former U.S. senator who had served as emcee said, "People kept coming up to me and saying they are tired. We cannot afford to be tired . . . We must never let the poor and minorities be hostage to any cause."