President Joe Biden on Sunday plans to sign into law a measure that boosts Social Security payments for current and former public employees, affecting nearly 3 million people who receive pensions from their time as teachers, firefighters, police officers and in other public service jobs. Advocates say the Social Security Fairness Act rights a decades-old disparity, though it will also put strain on Social Security Trust Funds, which face a looming insolvency crisis. The bill rescinds two provisions — the Windfall Elimination Provision and the Government Pension Offset — that limit Social Security benefits for recipients if they get retirement payments from other sources, including public retirement programs from a state or local government.