For all of you knuckleheads defending Mark McGwire, Sammy Sosa, Barry Bonds, etc by saying “it wasn’t against baseball rules,” steroids were banned by MLB in 1991…they just never tested. So yeah…they did break the rules.
From ESPN in December of 2012.
“Though steroids have been banned in MLB since 1991, the league did not implement leaguewide PED testing until 2003. The lack of testing meant it was unlikely players using PEDs would get caught.”