Let’s say that everybody participating in a sport takes steroids (which are illegal), would this be considered cheating? Or would this be allowed since it would still be an even playing field? Let’s say somebody would take steroids, but a drug test wouldn’t pick it up, so nobody would know about it?
The bottom line is that cheating is cheating no matter who is doing it and how many people are doing it. Unless there is an “unofficial” or “unwritten” rule that something is allowed, it is considered cheating. Cheating is defined by the *rules*; not by how level the playing field is or isn’t.
As for your second question, if the taking of the steroids is either illegal or not allowed by the sport, one would be forbidden from doing so, regardless of whether or not he got caught. As above, cheating is cheating.
Rabbi Moshe Rosenstein