The argument was basically "Mexico didn't say we couldn't do it based on the extradition treaty, even tho they were aware of the Ker doctrine under which we'd b

The argument was basically "Mexico didn't say we couldn't do it based on the extradition treaty, even tho they were aware of the Ker doctrine under which we'd be allowed to do this when the treaty was negotiated". So the argument was that there was consent (based on the Extradition Treaty). That is very, very different than them saying "We can kidnap someone from county X for reason Y without an extradition treaty in place." It was them basically saying "Mexico agreed to the unspoken terms that we'd use our legal precedents that preceded the treaty unless expressly forbidden to do so." So, Mexico consented by way of treaty and by not excluding forcible abduction (which was considered legal at the time the treaty was signed). That isn't the same as "did not consent". That is the Mexican government saying "Oops, we consented 60 years ago but we want to take it back now. We just forgot to mention it." https://www.aclu.org/safe-free/united-states-v-alvarez-machain https://www.aclu.org/safe-free/united-states-v-alvarez-macha... https://supreme.justia.com/cases/federal/us/504/655/case.html https://supreme.justia.com/cases/federal/us/504/655/case.htm... "(b) Neither the Treaty's language nor the history of negotiations and practice under it supports the proposition that it prohibits abductions outside of its terms. The Treaty says nothing about either country refraining from forcibly abducting people from the other's territory or the consequences if an abduction occurs. In addition, although the Mexican Government was made aware of the Ker doctrine as early as 1906, and language to curtail Ker was drafted as early as 1935, the Treaty's current version contains no such clause. Pp. 663-666."