He was exiled in 2232 for murder and unauthorized research (the research allegations revolved around some tampering with the pregnancy cycles in the Auto-Doc that apparently put all of Vault 8 in danger, but the details were deleted from the Vault 8 computer). His crime occurred many years after Richard Moreau's alleged crime, but Boyarsky only got as far as New Reno with a traveling caravan before he was robbed and killed by Reno thugs who saw him as an easy mark (which pretty much is true for everyone traveling from Vault City). His reasons for traveling south were unknown, but it is rumored his original destination was east of Reno - even though explorers report there is nothing out there except desert and deathclaws.