A federal judge early Saturday blocked Elon Musk’s Department of Government Efficiency from accessing Treasury Department records that contain sensitive personal data such as Social Security and bank account numbers for millions of Americans.

In an effort to slash government spending, President Trump has asked the world’s richest man, Tesla CEO Elon Musk, to lead his Department of Government Efficiency (DOGE). In turn, Musk and his team have spent the first few weeks of Trump’s second term waging a largely unchecked war on the federal bureaucracy — an onslaught that was finally challenged Thursday when a dozen states announced they would sue to block DOGE's access to government payment systems containing Americans' personal data.

Elon Musk's new position of special government employee is raising more questions than not. Here's what to know.