Bleacher Bums Forum

....That is something that should ruin a career.... 

Obviously, as to acts as a minor, it's way, way more complicated than "should ruin a career."  It depends.  Could this guy get certified as a doctor or lawyer, for example, down the road?  It depends. Maybe yes, maybe no. Here's the criteria recommended to state bar associations for lawyers by National conference of Bar Examiners:

"the applicant’s age at the time of the conduct, the recency of the conduct, the reliability of the
information concerning the conduct, the seriousness of the conduct, the cumulative effect of
conduct or information, the evidence of rehabilitation, the applicant’s positive social
contributions since the conduct, the applicant’s candor in the admissions process and the
materiality of any omissions or misrepresentations." Courts have often also
focused on whether the applicant expresses and demonstrated remorse. In order to be admitted to the bar
in such cases, the evidence of rehabilitation must show that the cause of applicant’s misconduct
has been eliminated, that such misconduct will therefore not recur, and that the applicant is
therefore currently fit to practice law.

MLB has a PR component to it.  Is it worth offending some fans by signing and playing a guy with this history?  Really doubt it's entirely a moral issue.  Clubs have to balance the PR hit and the conduct itself with maybe having a good player.