AMONG THE THINGS you will be buying when you pay your income tax sometime before fifteenth of April, will be a nice measure of convenience and economy for some journalist, lobbyists and others whose needs are not exactly acute. You will also be buying a nice little giveaway perk for members of Congress, who like to be able to hand things out in a way that may yield them some gratitude. Never mind that the munificent legislators are not actually footing the bill themselves. What they are "giving" away are free-subscriptions to the Congressional Record. As outlined in a news account in this paper Thursday, the congressional Record freebie system is little more than an exercise in favouritism, although it does rise on occasion to the status of a rip off. It should be junked.

By way of doing our own part, those subscriptions that have been coming to some people at The Post are being terminated - as they say, forthwith. But that will hardly make a dent in the larger problem. According to Thomas F. McCormick, the Public Printer, it would take $161 to cover the cost of a one year subcription. Subscribers, howevr, pay only $45 a year - that is, those who pay at all. The point is that most of the subscribers are the beneficiaries of some legislator's good will: there are only 4,400 paid subscriptions and 36,000 free ones; the free subscriptions are given away by senators, who are allowed to dispense 100 of them a year, and by House members who are allowed to dispense 68.

Who gets these free subscriptions? Well, journalists, politicians, lobbyists, schools, libaries, businesses, civic and other organizations - who knows? - your cousin Mergatroyd.You will note, in the first place, that the selection is arbitrary and, in the second, that need is not a criterion for receiving this largesse. Cutting out such subscriptions altogether, according to Mr. McCormick, would result in a saving of some millions of dollars.

The predictable response of those on the Hill, who wish to preserve the system, is that it is benign and wholesome because it lets the public know what is going on and helps in the education of schoolchildren and so forth and so on. But if that is the intention, surely some criteria of public need and public value should be put in place to guide the dispension of the Congressional Record. Yes, let's subsidize the publication, if we think that is a good idea, and let's also make it available free to some persons and institutions, if that seems right. But since good old John Q. is paying the bill, how about letting the Record be distributed in accord with some principles to which we can all subscribe, whether we subscribe to the Record or not. There is no public justification for letting senators and congressmen hand out these subscriptions as favors. It is a costly system with a phony rationale and an aroma of favoritism, and that strikes us as being more than sufficient grounds forending the system - now.