Forensic Analysts Accuse Billy Mitchell of Cheating for Donkey Kong Record

A new forensic analysis of controversial Donkey Kong world records claims those records were scored on an emulator and not on original hardware, essentially accusing the record holder of cheating.

The controversy revolves around Billy Mitchell, a well-known player who holds several records on classic arcade games such as Donkey Kong and Pac-Man, and the main character in the documentary King of Kong. For years, some people in the retro arcade game community have accused Mitchell of lying about his Donkey Kong records, prompting Twin Galaxies, an arcade game community that keeps track of high scores (among other things) and the Guinness World Records to strip Mitchell of its recognition, though the organization later reversed its decision.   

The new technical analysis focuses on Mitchell’s Donkey Kong records of 1,047,200 and 1,050,200 points. The author of the analysis is Tanner Fokkens, a hardware engineer and a competitive Donkey Kong player. His report was backed by five other experts. 

The crux of the controversy and accusations against Mitchell is that he claimed to have scored those records on original Donkey Kong arcade hardware, while his critics accused him of using MAME, an emulator that is recognized as a legitimate way to play the game, but records scored on these two different platforms are recognized as two different categories of records. 

“MAME scores which are passed off as coming from original arcade are disqualified,” Fokkens wrote in his report. 

Fokkens' analysis hones in on the differences between original hardware and MAME emulator in terms of video orientation, the screen transitions, new evidence that uses a high speed camera to show the scanning of video memory, and the presence of V-sync tearing—essentially “a horizontal split at one or more places of the image”—in the tapes Mitchell submitted to claim his records. 

“These transitions are like a fingerprint of the platform the game was played on,” Fokkens wrote in his paper. 

Fokkens told Motherboard in an email that “the smoking gun since the beginning of the dispute in 2018 was always the transitions.”

These transitions are when the game goes from the screen prefacing the stage to the stage itself, which happens gradually—takes several video frames—as the CPU draws the “the graphical elements of the stage into video memory,” Fokkens explained in his email. 

The video memory, or VRAM, Fokkens said, “can be thought of as a book that contains the description of what the stage looks like.”

“Just like how a person reads a book, video hardware reads VRAM left to right, then down a line, and then it repeats until the bottom of the page is reached,” he said. “The arcade hardware’s video generator reads each page only one word at a time, but the words throughout the page are changing as the CPU is revising the text, even while it is being read.”

On the other hand, if a player uses an emulator, “instead of reading the book one word at a time, MAME takes a snapshot of the entire page and displays all the words from a single moment in time on the screen,” Fokkens said. This is what causes the different video transitions in MAME and arcade, “and ultimately how Mitchell’s tapes were found to not have been recorded on arcade hardware.”

“It is impossible for unmodified arcade hardware to produce the transitions that are shown in Billy Mitchell’s taped footage,” Fokkens said. “Given all this evidence, and Billy’s continued insistence that he did not play on MAME, it is my opinion that he is not being truthful in his representation of his 1,047,200 and 1,050,200 gameplay tapes.”

The controversy over Mitchell’s records is so serious that the player has sued Twin Galaxies, a video game forum and the organization that supplies the Guinness World Records with certified records, for defamation. The case is still ongoing.

Lawyers representing Mitchell in the lawsuit did not respond to a request for comment. 

UPDATE, Sept. 9, 12:04 ET: A previous version of this article incorrectly stated that Fokkens analysis shows “new evidence that allegedly shows Mitchell used a high speed camera to scan video memory.” In fact, it shows “new evidence that uses a high speed camera to show the scanning of video memory.”

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