Modifies provisions relating to an income tax deduction for certain National Guard duties

HB 1438 allows Missouri taxpayers who serve in the National Guard or reserve components of the U.S. Armed Forces to deduct a growing percentage of their military income from their state taxable income. The deduction starts at 20% for 2020 tax years and increases annually to 100% by 2024, covering income from training, annual drills, and bonuses for joining/re-enlisting (effective 2025). It also adds a 100% deduction for state-funded National Guard duties (SAD/SED) starting in 2026. The bill excludes deductions for civilian federal service, such as uniformed civil positions. This directly benefits Missouri military members and their families by reducing their state tax burden.