13 Democratic state attorneys general and Washington DC have expressed support for a federal lawsuit by the Mexican government against a group of eight US gunmakers and distributors, which they accuse of fueling gun violence by facilitating the trafficking of weapons to Mexican cartels. Mexico alleges that the companies have been fully aware that their products are trafficked into the country, and argues they have a duty to ensure their products are used safely.

The case itself is a test of the Protection of Lawful Commerce in Arms Act (PLCAA), which shields gun manufacturers from both lawsuits (procedural law) and liability (substantive law). In short, Mexico - and the US attorneys general - are asking the District Court of Massachusetts - to rule that PLCAA's protection is not unlimited, and that this lawsuit seeking to hold them liable should be allowed to proceed.

As Scott Graber writes in Just Security:

The filings discuss a threshold issue that the court must soon resolve, which has been the subject of significant previous coverage on Just Security: whether the 2005 Protection of Lawful Commerce in Arms Act ("PLCAA"), which immunizes gun companies from certain suits, bars Mexico's lawsuit. Amidst this attention, one piece of the puzzle just beginning to be argued in the filings is the potentially dispositive role that choice-of-law rules will play in answering that question.