Given the legal dangers facing Donald Trump and his penchant for making deals, there is an obvious approach. Biden could offer Trump immunity in return for an end to his refusal to transition his administration to the Biden Administration. Specifically, the New York Times has presented convincing evidence that Trump is guilty of evading taxes for years. The New York District Attorney is currently investigating Trump and his businesses. Michael Cohen, Trump's personal attorney's conviction for federal campaign violations involving payoffs to two of Trump's mistresses, identified Trump as an unnamed co-conspirator. And the Mueller report presented evidence of Trump's obstruction of justice even though the Department of Justice did not indict him because he was a sitting President.
According to press reports, Biden has told members of his inner circle that he does not want to pursue Trump. Biden believes pursuing Trump would consume too much of his administration's attention, make it harder to work with Republicans in Congress and undercut his efforts to unite the country. These reasons are like those given by President Obama when he announced his decision to forego an investigation of the Bush Administration's use of "enhanced interrogation." Presumably, Biden would attempt to deflect attention from his decision by claiming that he will leave the decisions about criminal investigations to his attorney general. But the decision about whether to pursue Trump's wrongdoing is a policy decision that only the President can make. And if Biden is not going to have Trump investigated with an eye toward criminal prosecution, then he might as well get something concrete for the reprieve. At least, Trump's acceptance of a pardon would be an admission of guilt.