Editorial: Hunter becomes hunted: Joe Biden must let professional federal prosecutors in Delaware go wherever the evidence leads

Hunter Biden has told the world he’s just learned his “tax affairs” are under investigation by Delaware’s U.S. attorney. The burden is now on his father, President-elect Joe Biden, to ensure the nation that his attorney general and federal prosecutors will follow the evidence wherever it leads.

First, to dispense with the pro-Trump conspiracy theories predictably choking the internet: No, there was no deep state plot to boost Biden by withholding potentially explosive information during campaign season. Rather, the Justice Department made good on rules that bar prosecutorial meddling in elections, in stark contrast to the many mistakes made by Jim Comey in 2016.

Now comes Joe Biden’s integrity test. Over the course of the past year, he has rightly castigated the incumbent and his attorney general, Bill Barr, for turning the Justice Department into a Trump protection racket. Before Barr spoke the truth that there’s no evidence of systemic fraud capable of overturning the election results, he went out of his way to aid Trump and his allies foreign and domestic, including Michael Flynn, Turkish president Recep Tayyip Erdogan and others.

In a now-infamous dinner with Comey, Trump pressed the FBI director for a vow of loyalty. He eviscerated his first AG, Jeff Sessions, a former Trump campaign insider, for having had the good sense to recuse himself from investigating the Trump campaign’s Russia ties. So too did it stink of intimidation or retaliation when Trump forced out Preet Bharara as Manhattan’s U.S. attorney, then Barr removed Geoff Berman from the same job.

Biden, on the cusp of picking his own attorney general, purports to revile the way Trump has laid waste to the Justice Department’s independence. He must reiterate that now — and promise investigations and, if appropriate, prosecutions on the straight and narrow, even of his own son.