WASHINGTON — Donald Trump’s early announcement of his third White House bid won’t shield the former president from the criminal investigations already confronting him as an ordinary citizen, leaving him legally and politically exposed as he seeks the 2024 Republican nomination.

The Justice Department is pushing ahead with its probes. And with the midterm elections now mostly complete and the 2024 presidential campaign months away from beginning in earnest, federal prosecutors have plenty of time to continue their work even as Trump hits the campaign trail. ...