Rep. James H. Scheuer (D-NY.) has informed Attorney General William French Smith that he has uncovered new and possibly damaging evidence in the Justice Department's criminal conflict-of-interest investigation of Guy W. Fiske, who resigned this month as deputy secretary of Commerce.

When he was at the department, Flake oversaw debate on a proposal by the Communications Satellite Corp. (Comsat) to sell the nation's weather satellites to a private company. Comsat was the only company to offer to purchase the satellites.

At the same time that Fiske was overseeing debate on the Comsat proposal, he was meeting privately with Comsat officials about a job at the company.

After Scheuer's House subcommittee on natural resources began an investigation of Fiske's dealings with Comsat, Fiske removed himself from any further part in the satellite matter. Fiske resigned as the second-ranking official at Commerce after the Justice Department began its investigation.

Fiske has said his job discussions with Comsat ended before he came to Commerce in June, 1982, with the exception of one meeting with Comsat president Joseph V. Charyk last November.

In his letter to Smith, dated Monday, Scheuer wrote that he had learned of events "which I believe carry a strong presumption of Mr. Fiske's active and knowing involvement in activities that constitute a violation" of the criminal conflict-of-interest statute. "This information also appears to contradict public statements Mr. Fiske has made, the testimony he submitted to our subcommittee, and statements he apparently made to both the secretary of Commerce and the Commerce Department's general counsel;" Scheuer wrote.

The letter included two pages of transcripts of handwritten notes by R. Blair Murphy, an executive recruiter hired by Consat who negotiated with Fiske and Charyk.

According to Murphy's notes, Fiske actively sought the presidency of Comsat over a 12-month period, ending this March."

In addition, the notes indicate that Murphy discussed the proposed satellite sale with Fiske and Charyk separately, in what Scheuer called a "triangular fashion."

Scheuer said that Murphy's notes, in conjunction with other documents his subcommittee has, "seem to indicate more than mere appearance of conflict of interest" that Commerce officials had found. Scheuer also disputed Fiske's assertion that he had little or no policy role in the proposed satellite sale.

Fiske could not be reached for comment last night. In the past, Fiske has denied any impropriety, saying that he was only an "expediter" of the proposed sale and that the job discussions "never reached the point of actual negotiations."