Trump's constitutional power to unilaterally grant clemency was on display this week, as the president announced a forthcoming pardon for conservative commentator Dinesh D'Souza, as well as potential clemency for celebrity lifestyle guru Martha Stewart and disgraced former Illinois Gov. Rod Blagojevich.
With his five pardons so far, Trump has waded into a decades-long feud between the Department of Justice and at least three previous White House administrations over the process that determines how one of the presidency's most powerful tools is used.
Trump has used the pardon power to reward friends and punish foes, earning the ire of ethics watchdogs. But in the process, he has wittingly or not claimed back power for the president from the Justice Department, which has sought to expand its influence over the pardon process in recent years.
The White House and the Department of Justice did not respond to a request for comment.
"In the recent era, the last 40 years or so, you had the Justice Department pretty aggressively trying to take control of the pardon process," Samuel Morison, a former lawyer in the office of the pardon attorney, told CNBC. "I was there for 13 years, I knew exactly what was happening."
The dominance of the Justice Department in the pardon process has led to problems. An inspector general report published in 2012 found that former Pardon Attorney Ronald Rogers withheld information from President George W. Bush that may have led to a commutation. It has also led presidents, notably Bill Clinton and Barack Obama, to refrain from using their pardon power until near the end of their term.
The rate of presidential pardons has declined over the same period. According to an analysis of Justice Department data, the approval rate for pardon petitions declined from about 33 percent under Carter to less than 10 percent under both Obama and Bush.
Trump's five pardons already make him an outlier: None of his three predecessors issued any pardons in the first two calendar years of their term.
In 2010, when then-White House Counsel Gregory Craig wrote a memo seeking to modify the pardon process to make it more responsive to the president, the DOJ killed the plan, according to a 2016 article written by Margaret Love, who served as U.S. pardon attorney for seven years.
Love argues in her article that the office of the pardon attorney, which is part of the Department of Justice, should be moved to the direct supervision of the president. It's a plan that, while she was in the Justice Department, Love did not believe was viable.
Three former Justice Department officials, including Love and Morison, as well as another who asked not to be identified because the memo is not public, said they were familiar with Craig's memo, which was described as being about 40 to 50 pages long. CNBC has not obtained a copy of the memo.
Craig did not respond to a request for comment left with Columbia Law School's office of media relations, and could not otherwise be reached by CNBC. Craig left the law firm Skadden, Arps, Slate, Meagher & Flom last month without explanation, according to Bloomberg Law. Skadden did not respond to a request for comment from CNBC.