When Joe Biden is sworn in as president on January 20, he will be forced to tackle an issue that may define his presidency as much as the health and livelihoods of the American people: the fate of his predecessor, Donald Trump https://on.ft.com/3r7ysL5 

It’s no secret that Trump has tested and twisted the US political system to breaking point, serving as a one-man crash course on the US constitution and legal and ethical norms.

A big question remains: should Washington prosecute a former president? https://on.ft.com/3qXkon7 

While in office, Trump has been protected by the Department of Justice numerous times. For instance, the DoJ helped the president stall a state criminal investigation into possible tax fraud https://on.ft.com/3qXkon7 

Those protections fall away in just over a month from now, leaving Trump’s fate in the hands of his political opponents and, should they proceed, ultimately the courts.

With that in mind, no former US president has ever faced prosecution http://on.ft.com/3qXkon7 

The president’s conduct before and while in office offers potential targets for possible federal investigation.

Most notably, Robert Mueller’s investigation into the 2016 Trump campaign found several instances of possible criminal obstruction of justice http://on.ft.com/3qXkon7 

While Trump has wrecked the norms that kept the DoJ at a political distance from the White House, Biden has pledged to restore the walls that previously existed http://on.ft.com/3qXkon7 

It begs the question: will Biden pursue an investigation into Trump?

He's steadfastly refused to say one way or the other whether he believes Trump should be prosecuted — and he certainly does not want it to be the centerpiece of his administration http://on.ft.com/3qXkon7 

You might also be wondering: ‘Can the president pardon himself?’

The short answer is 'no', but a 1974 DoJ legal opinion raised the idea that a president could temporarily give their powers to their vice-president for the purposes of a pardon http://on.ft.com/3qXkon7 

Trump will leave the White House with potential personal criminal liability unlike any commander-in-chief since Richard Nixon, but will he be prosecuted?

Or will an investigation be used as one of the grievances to paint a potential comeback in 2024? http://on.ft.com/3qXkon7