I think we actually agree more than we disagree, only your added refinement makes the difference between properly enforceable state or national law and tribal custom more clear.
Within the tribal framework, tribal custom should be able to decide on matters of property, etc. But Tribe A shouldn’t be able to “give” one of it’s members to Tribe B against that member’s will, because that individual’s right to personal freedom trumps the tribe’s right to observe its custom. Allowing that case of “slavery” to exist would be a contravention of the law of the land.
The difference in this case is that the Papua New Guinea court did not step in to tell the tribe what to do; the woman went to the court to seek protection. This woman clearly did not accept this “custom” as valid, for whatever reason. She has as much right to seek a remedy in the national courts as anyone else in the country.
I didn’t say dictatorship of the minority, I said tyranny. By setting themselves and their territory apart they create state within the state. This infringes on the UDHR by inhibiting the equal and fair treatment of all men and women in all parts and instances.
As I said it’s fine to have subsets of laws as long as these are subject to the greater laws of the state and that these are in keeping with the UDHR. The case in the OP and the Pakistani case are instances where this is obviously not the case. By the application of these tribal laws human beings are not warranted equal freedom and protection under the law.
As involuntary members of the tribe they have no choice but to subject themselves to the whim of the leadership, if the state does not intercede on their behalf. In my opinion the state should not only intercede in the specific case, but also, as in the Pakistani situation, pursue those that strive to uphold the tribal laws that are in conflict with state law. To condemn someone to be criminally victimized is the same thing as perpetrating the crime.