Twice in the past several days {Charles Krauthammer on July 3 and Jeane Kirkpatrick on July 6} The Post has provided space for defense of Assistant Secretary of State Elliott Abrams and castigation of Democratic House members calling for Mr. Abrams' resignation. As the author of the letter of 129 Democrats to Secretary of State George Shultz, let me reply.

Despite Mr. Krauthammer's and Mrs. Kirkpatrick's attempts to shift the focus to the case for supporting the contras, the key issue remains the Constitution. The question is not whether we end up supporting the contras, but how we collectively go about making that decision. This is where Mr. Abrams went astray and why he must go.

Mr. Krauthammer admits that Mr. Abrams both directly lied to Congress and also placed a higher value on keeping faith with the sultan of Brunei than with Congress. (He curiously adds that if Mr. Abrams is guilty then Secretary Shultz is just as guilty since he was also part of the Brunei pact.) Mr. Krauthammer also dismisses the calls for Mr. Abrams' resignation by 129 congressmen as simply motivated by the desire to stop contra aid, not by any concern for process.

Mrs. Kirkpatrick stresses that there has been little financial corruption and laments the amount of public attention given to the Iran-contra hearings when no "crime" was committed comparable to the break-in of Watergate. She also castigates Congress for not "honoring" the U.S. commitment to Brunei and Saudi Arabia.

But how were these commitment made? Not by consultation with Congress as the Constitution requires. And that is the basic point that both Mr. Krauthammer and Mrs. Kirkpatrick miss.

The administration's present problem with Congress is far more serious than any financial impropriety or disagreement on policy. It is the administration's continued contempt for the constitutional role of Congress in shaping foreign policy that has caused so much animosity.

In the case at hand, it is Elliott Abrams' continuously duplicitous treatment of Congress that requires his departure. Not only did he downright lie to Congress when he assured us that he was "not in the business" of soliciting third-country money for the contras, but he purposely contrived ignorance to Congress about the Hasenfus flight and other Ollie North activities. His belated explanation was that he purposely didn't ask Lt. Col. North questions he didn't want to know the answers to, yet he let Congress think he had all the relevant facts. Col. North testified Wednesday that Mr. Abrams never asked him about U.S. government involvement in the flight, but he "didn't have to ask me -- he knew." Yet for 18 days Mr. Abrams categorically denied anygovernment involvement in the flight.Our constitutional system of shared responsibility for foreign and domestic policy requires full and honest testimony from the executive branch. From Elliott Abrams we have had neither.

His remaining at his post reveals clearly this administration's disregard for constitutional sharing. That is why Mr. Krauthammer's and Mrs. Kirkpatrick's attempts to shift the focus on Mr. Abrams from the Constitution to the contra aid policy missed the point of congressional displeasure.

JIM MOODY U.S. Representative (D-Wis.) Washington