Chicago Mayor Eugene Sawyer called for appointment of a special prosecutor to determine whether State’s Atty. Richard M. Daley’s staff turned in phony signatures on referendum petitions after the Chicago Tribune reported “strong evidence” that employees of Daley and others violated election laws in 1985 and 1986. The paper said Daley staff members or their relatives circulated petitions and turned in the names of people who later said they had not signed. The petitions sought to place on the ballot a choice between a two-party primary system or a nonpartisan general election. Daley is considered the front-runner for the Democratic mayoral nomination.