WHEN THE Supreme Court handed down its first one-person, one-vote decisions, Justice Frankfurter warned that the judiciary was in danger of entering a "political thicket." At first he proved a poor prophet: after the 1970 Census, most legislatures redistricted without much fuss, and the courts approved most of their plans. Now, after the 1980 Census, some federal courts seem in a rush to enter the thicket most of them wisely avoided a decade ago, and the Supreme Court has been invited to follow. Before that happens, the courts need to understand better what is--and is not--at stake in the redistricting process.

What is at stake is--indisputably--political. There is no more political decision than the drawing of legislative district lines, no decision more vital to politicians, legislative leaders and political parties. And there is--though a few professors, armed with computer programs and page-long equations, would argue otherwise--no single non-political way to draw the lines. For instance, if you divide the city of Dallas by north-south lines, you will create two Democratic districts and one Republican; if you use east-west lines, the districts will be 2 to 1 Republican. Which way is fairer? Democrats and Republicans each give a dozen justifications for their lines. There is no self-evidently correct neutral principle to decide such cases.

Naturally, the losers in the political process try to reverse the result in whatever way they can-- which usually means they file a lawsuit in what they think is a friendly court. They allege (correctly) that the plan adopted by the majority favors the majority's political interests. It is here that the courts need to summon the restraint to say that if the equal population standard is met and if the plan meets the test of racial fairness the plan should be approved.

But, you may ask, what about the dangers of gerrymandering? Shouldn't the courts put some limits on the extent to which the majority can favor itself? The answer is, they already have, through the one- person, one-vote rule. The equal population standard, without any further rules, imposes a very tight discipline on the redistricting process. However ingenious the redistricter, he is unlikely to produce a plan that, over the 10-year period the typical redistricting plan is in effect, will bar the opposition from winning control. That was possible when legislators did not have to meet the equal population standard and were allowed to use other rationales-- adherence to local government boundaries, historical continuity, representation of particular parts of a state --to justify their plans. But the history of redistricting under the equal population standard is full of Democratic plans that produced Republican majorities and vice versa.

Courts sometimes enter the political thicket when legislatures fail to act, and some seem in a hurry to do so; courts have redistricted Colorado's, Missouri's, and Minnesota's congressional districts although their primaries are not scheduled until August or September. They would have done better to put pressure on the parties to reach agreement. Why do the courts seem so ready to meddle? Partly because of a natural human inclination to meddle, to improve; and partly because the importance of redistricting has been overstated by the politicians themselves. As a result of the politicians' shrieks and warnings, some judges appear to have been convinced that control of the political system itself is at stake in the redistricting process.

It isn't. Redistricting changes the odds, shifts the battlegrounds, revises the cast of characters. It may end prematurely the careers of some useful legislators (as happened in Illinois this year). It can give a party a marginal advantage. But over the long haul, under the discipline of the one-person, one-vote rule, even the most partisan redistricting plan cannot prevent the will of the voters from being reflected with reasonable accuracy. There is no need for the courts to enter this political thicket, except to prod the politicians into doing what is--quintessentially--their job.