The lingering suspicion that thousands of immigrants were rushed into citizenship without proper procedures or checks prior to the 1996 election is fueling debate over enumerating the nation's population in the 2000 census. Miscounts could lead to serious skewing of political and economic trends.

Republicans are wary of the Census Bureau proposal to use sampling to estimate facts about households that fail to return census forms. Rep. Dennis Hastert (R-Ill.) has called sampling "a risky scheme ripe for political tampering."

There are Constitutional questions involved also.

• The U.S. Constitution calls for an "actual Enumeration" of the population -- a tricky point between legal scholars and sampling advocates.

• But the return rate for forms has been falling, from 78 percent in 1970 to just 65 percent in 1990 -- a gap which may be even wider in 2000, and even less easy to bridge through sampling.

• Some professional pollsters contend that, handled properly, sampling can produce a reasonably accurate and reliable count.

The suggestion is being made that the Census Bureau's work be supplemented by an independent audit. That would be accomplished by a Congressionally-established commission, with equal representation from both parties, charged to work with the Bureau to improve its methodology and execution.

Supporters of this approach say a highly professional staff must be hired, one insulated from political pressures. One estimate of costs involved range from $5 million to $20 million. The entire Census is projected to cost more than $4 billion.

Source: Everett Carll Ladd (Roper Center for Public Opinion Research, University of Connecticut), Wall Street Journal, July 30, 1997.