I know; it sounds like a story about Klingons....
Looking over that web page of "Repeat Offenders" which I mentioned in my "Jury Prudence" post, I found this bit o' trivia: over the many years that 'Law & Order' has been on the air, three different actors have played Borak the medical examiner:
Timothy Britten Parker
Josh Pais Chip Zien was the first to play the role, in the first season episode "Happily Ever After". (Slightly off-topic, I wonder if the casting director had Zien in mind for that episode because he made a connection between "Happily Ever After" and "Into The Woods", the Sondheim musical about fairy tales?) Then Timothy Britten Parker took on the role in the second season episode "His Hour Upon The Stage". But then he was AWOL from the series until the 13th season, in which he returned as Borak in the episode "Mother's Day". Between those two appearances, Josh Pais played Borak from "American Dream" in the fourth season to the 13th season episode of "True Crime". Pais also played an unnamed medical examiner in two first season episodes - "Poison Ivy" and "Mushrooms". But to reduce the surplus population of Toobworld, I think we can safely assume that both of these were also Borak.
'Law & Order' is probably the most unadorned of TV shows; in the relative terms of television, it's probably the most "realistic". So even though it shares the same dimension as - and is closely linked to - 'The X-Files', 'Law & Order' doesn't lend itself to wild Toobworld splainins for recasting characters, like quantum leaping or alien impersonations.
Therefore, to clear up this case of recastaways, I'm going to suggest that all three Boraks were members of the same family who went into the same line of work. I have no problem thinking of them all as brothers; I've seen worse casting when it came to finding genetic similarities.
An interesting side-note: both Pais and Parker played a character named Cioran in first season episodes of 'Law & Order'. (First Pais in "The Reaper's Helper" and then Parker in "Life Choice" nine episodes later.) I admit I haven't done the research to find out who Cioran was and if they should be considered the same character or not.)