LAST SPRING it appeared that the Senate would soon fulfill the pledge it made in 1977 to protect its employees against job and salary discrimination. After months of deliberation, the Government Affairs Committee has approved a propoasl creating a fair employment practices program - the unfinished business left from the code of ethics the Senate adopted for itself last year. The fair-employment measure was sensitive to both the employment rights of workers and to the special political workings of the Senate. And its passage seemed ensured: What senator would want publicly to support continuation of the Senate's documented discriminatory employment practices? Well, now no senator will have a chance to vote on the measure at all this year because the Democratic leaders have decided not to bring it to a floor vote before the Senator adjourns.

The Democratic Policy Committee and the party's chairmen of major committee are responsible for this non-unexpected, but nevertheless disappointing, decision. Their action will likely slow the push for a similar measure in the House, which now has only a voluntary structure for investigating discrimination complaints. Significantly, the senators reached their decision during a closed meeting and by consensus rather than by vote - the better to leave no particular senator's tracks.

Some members have contended that the Senate's calender is just too crowded to give the measure consideration now. Nonsense. The proposal has been under study for over a year. It is not complex. It already had been fine-tuned and approved by two committees. As it amounted to only the creation of a formal grievance panel with authority to judge complaints and to seek ways of improving fair-employment practices, it should have provoked little, if any debate on the floor. The simple truth is that the Senate's Democratic leadership did not want the measure voted on this year. In other words, they wanted to delay the time when the Senate, and the House as well, will have to abide by the same hiring policies Congress has legislated for everyone else.