washington

The US Congress is expected to pass legislation in the near future restricting foreign scientists' visits to nuclear-weapons laboratories. The move is a response to accusations of spying by China, which reached their peak last week with the release of a report by a Congressional committee chaired by Christopher Cox (Republican, California).

Scientific societies are working to influence the legislation, which is certain to be passed in response to the scandal. Despite public expectations of a clampdown on partnerships with foreign scientists, laboratory officials and the societies are confident that the legislation will be framed so as to allow partnerships to continue.

Critics of the Clinton administration in Congress are talking about clamping down on foreign visits to the laboratories, but in practice their room for manoeuvre is constrained by the need to keep the weapons laboratories scientifically competitive.

“The Congress is attempting a legislative fix to a problem that isn't amenable to a legislative solution,” says an official at one scientific society. “A large number of people, including foreign scientists, come into occasional contact with people who do the classified work. There is no way to stop that without harming the US nuclear weapons programme.”

Defence bills passed by the Senate, and expected to be passed by the House of Representatives after the recess, include special provisions on laboratory security. The laws will impose conditions on visits by scientists from so-called ‘sensitive countries’ to the three nuclear weapons laboratories: Lawrence Livermore in California, and Sandia and Los Alamos in New Mexico.

A proposal from Jim Ryun (Republican, Kansas) would drastically curtail foreign visits to weapons laboratories. But a more pragmatic package proposed by Norm Dicks (Democrat, Washington), the senior Democrat on the investigative committee, and backed by Cox, is likely to form the basis of the final legislation, observers say.

Under this proposal, visitors to the laboratories from the sensitive countries, which include Russia, China and India, would face a 60-day moratorium until new vetting procedures have been implemented.

The parts of non-weapons laboratories which these scientists normally visit will not be affected. But some of these, including Brookhaven, have already stepped up their vetting procedures in response to the Chinese spying scandal.