Final answer:
Federal agencies are regulated by laws such as the Privacy Act of 1974 and the Financial Services Modernization Act of 1999, and operations such as the National Security Agency must abide by the Fourth Amendment's protections against unreasonable searches and seizures. The EU's GDPR provides an example of even stricter data privacy rules.
Step-by-step explanation:
The mechanism that ensures personal information collected by Federal agencies is limited to what is legally authorized and necessary, and is maintained in a manner that precludes unwarranted intrusions upon individual privacy, includes several laws and regulations. Amongst these, key legislation such as the Privacy Act of 1974, Financial Services Modernization Act of 1999, and regulatory entities like the National Security Agency (NSA) within their constitutional confines, ensure that personal information is handled properly.
Additionally, federal agencies are bound by the Fourth Amendment, which protects citizens against unreasonable searches and seizures, requiring probable cause and a warrant issued by a judge to access private digital information. Countries like those in the European Union enforce even more strict regulations on data privacy through the General Data Protection Regulation (GDPR).