The U.S. Supreme Court has upheld the IRS’s authority to access crypto exchange data by declining to hear James Harper’s appeal. This decision supports the use of “John Doe” summonses, allowing the IRS to obtain user transaction records from platforms like Coinbase without individual warrants. Privacy advocates, including Coinbase and Elon Musk’s X, argue this undermines Fourth Amendment protections and expands government surveillance powers. The ruling reinforces the IRS’s ability to investigate potential tax evasion in crypto markets while intensifying concerns about user privacy and regulatory overreach in decentralized finance. It sets a major precedent for crypto-related data access enforcement.