The Windfall Elimination Provision is designed to prevent higher earning state and local pensioners from being treated as low income earners for the purpose of computing social security benefits. Someone who had a part of their career in the SS system but also a part in a non-SS public pension system would look to the SS system like a low income earner.
SS Benefits are computed as a share of inflation adjusted average income; that share is higher for low earners. The WEP provides that if an apparent low earner also receives a pension, they won’t get the bump for low earners. Phase-in of this provision is largely over, so most currently beginning retirement are affected. The provision does not apply to survivor benefits. There is no reciprocal offset or reduction in state or local pensions.
A non-working spouse is entitled receive an amount equal to 50% of the worker’s benefits. The SS Benefit of a spouse is reduced dollar for dollar by an SS benefit that they receive based on their own earning record — there is no marriage penalty. This has always been the law. Under the Government Pension Offset the SS benefit of a spouse is also reduced dollar for dollar by a pension benefit that the spouse receives from a job where he does not contribute to social security.