Lyn Nofziger's defense attorneys filed motions yesterday to set aside the former presidential aide's illegal-lobbying convictions on the grounds that prosecutors failed to prove he violated the law.

The defense also pleaded for a new trial, saying U.S. District Court Judge Thomas A. Flannery erroneously instructed jurors in how to determine if the issues Nofziger lobbied about were of "direct and substantial" interest to the White House.

Nofziger, 63, was convicted Feb. 11 of three counts of illegally lobbying former White House colleagues on behalf of Wedtech Corp., a maritime engineers union and the manufacturer of the Air Force A10 antitank plane.

The former White House political director faces a potential two-year prison term and a $10,000 fine for each of the three convictions. He is scheduled to be sentenced March 25.

In its motions in U.S. District Court, the defense repeated contentions made throughout the four-week trial that the prosecution team headed by independent counsel James C. McKay failed to prove that the issues Nofziger raised with former colleagues were "particular matters" of "direct and substantial interest" to the White House.

"The gross insufficiency of the evidence mandates that the guilty verdict . . . against Mr. Nofziger be set aside and that a judgment of acquittal be entered," defense lawyer Robert Plotkin and E. Lawrence Barcella said in their pleadings.