The IRS attempted to share immigrant tax data with ICE under a 2025 agreement, sparking documented fears that have caused a measurable drop in tax filings—one Maryland accounting firm lost 15% of clients. Federal courts have since blocked the data-sharing practice citing privacy violations, but the damage to compliance is already visible. The real issue isn't whether data is currently being shared (courts halted that), but rather whether that initial breach has permanently eroded immigrant trust in the tax system, potentially costing the government billions in lost revenue from undocumented workers who have historically paid $90 billion annually.