To elaborate the question of "Can-a-jew-be-polygamous".
If a married Jew makes Kosher second Kiddushin:
Do they hold legally (קידושים תופסים, she's married and needs a Gett to be divorced)?
Can the husband be legally intimate with her?
Is he a subject to lashes or other Bet Din punishment?
Does the court force him to divorce either wife?
Is there a difference b/w the Ashkenazi and Mizrahi traditions?
Does it matter in which country the second Kiddushim are made?
Most intriguing, as there are many theoretical Halachic views and opinions, what would be done practically in the case that it would happen in Jerusalem for an unaffiliated Ashkenazi Jew?