A coalition of New York mayors is debating whether to push for changes to state labor law that would give fiscally troubled cities more negotiating leverage with public-safety unions before binding arbitration, the Wall Street Journal reported yesterday. A proposal gaining traction with the mayors of Syracuse, Rochester, Albany and Yonkers would require arbitrators to give more weight to a city's finances when imposing a binding contract. Among the factors would be whether a city can pay for salary increases and health insurance plans without raising taxes or cutting services.