Awarding contracts to the lowest responsible bidders, some of whom may be nonunion contractors, is a means to that end.

Bids are solicited from contractors based on these documents; a contract is then awarded to the lowest responsive and responsible bidder.

State law requires that government contracts be awarded to "the lowest responsible bidder," but it gives New York City an exemption.

Transit officials, however, said they still viewed Lockheed as a responsible bidder.

"Contracts funded with public money must always be awarded to the lowest responsible bidder," said an association official, Donald E. Sours.

"The law says you must choose the 'lowest responsible bidder,' " he said.

Invitations for Bid require the submission of sealed bids, publicly opened, with award to the low, responsive, responsible bidder.

(The law does allow the city to select the lowest responsible bidder.)

Salem also said inquiries from "financially responsible" bidders would be welcomed.