FOR MOST OF THE last decade, the House Judiciary Committee sat on its hands while the Senate and countless legal scholars struggled with codifying the federal criminal law. Let the Senate act first, Chairman Peter Rodino used to say, and then the House would get to work. The Senate did act first, passing a new criminal code last January. And the House committee has gone to work. But the subcommittee to which that work has been assigned seems totally unable to handle it.

The subcommittee, headed by Rep. James R. Mann (D.S.C.), is proceeding as if nothing had happened during the last 10 years. Its members either do not know about or are choosing to ignore the huge amount of scholarship that lies behind the Senate bill. They began at the beginning - where the Brown Commission began in 1967 - by working their way through the existing criminal laws, section by section. That's a job they could have undertaken at any time in the last 25 years, without waiting for the Senate and without creating the Brown Commission. If the subcommittee continues its present approach and pace, it may reach the point in 1988 that the Brown Commission reached in 1968.

The conclusion that flows almost inevitably from the subcommittee's proceedings is that the House Judiciary Committee has no intention of producing a new criminal code this year - or any other year. It may produce a bill, sometime, that tinkers with the legislation now on the books. But it appears intent upon flushing down the drain a decade of sustained effort. All the talk, and it has been almost universal, about the need for a new code seems to have fallen on deaf ears.

There are three broad categories of objection in the House to serious consideration of any new criminal code, including the Senate's version. One is that expressed by Rep. V. Lamar Gudger (D-N.C.), who says House members don't want "to come along and rewrite these statutes after all years." How different that is from the view of the House in 1966, when it put this massive re-writing process into operation by voting to create the Brown Commission. And how different it is from the view of Richard H. Poff, then an important figure on the Judiciary Committee and a member of the Commission. He explained that a new code was esential because the existing law "is a haphazard hodgepodge of conflicting, contradictory, and imprecise laws piled in stop-gap fashion one upon another with little relevance to each other . . ." Rep. Gudger and those he says agree with him would leave the law in that condition.

The second type of objection is that made by Rep. Elizabeth Holtzman (D-N.Y.). She says, "Many times we found there was no explanation for what the Senate had done." We find it next to impossible to believe that the required explanations are not somewhere in the volumes of material generated by the commission, the Senate Judiciary Committee and the law-schol presses. True, some may be hard to find. But we have never had any difficulty finding them - perhaps because we were willing to ask those have spent years with the project where the explanations were to be found. The House subcommittee, unfortunately, has chosen not to ask and, as far as we can tell, not even to look very hard.

The third objection is serious consideration of the Senate bill in the House is the claim that it vastly expands federal jurisdiction. We regard this as a phony. The expansion is more apparent than real because the Senate bill makes the already large federal jurisdiction look even larger by putting it all together, instead of scattering it all over the place in the manner of existing law. And the fact is that many of those making this argument now were warm supporters of the Brown Commission's version of the new code and never spoke one word against its jurisdictional approach. But when that approach was carried over, almost intact, to a Senate bill that had other provisions they did not like, it became the object of their ire.

The performance so far of Rep. Mann's subcommittee ought to embarrass the full Judiciary Committee, especially two of its senior members, Reps. Robert W. Kastenmeier (D-Wis.) and Don Edwards (d-Calif.), who served on the Brown Commission. They, at least, should understand the need for a new code and the foolishness in which the subcommittee is engaged.