I found it really astonishing that undocumented migrants were kidnapped so routinely, that it was such a commonplace part of the journey for people trying to reach the US, and that we hear almost nothing about it here.

I think the daily challenge for a lot of beat reporters is, how do you get past the regurgitated sound bites of powerful people or evasion masters who are so used to this routine - the theatricality of press conferences and stage-managed interviews and teams of handlers?

I wanted to think about ways to get an American readership concerned with what is happening in Mexico, but also to reframe it as a problem Americans share.

One thing I've discovered is that if you remain in contact with people, if you build longitudinal relationships, if you invest in sources who seem at first like they're uncomfortable or unwilling to talk, if you keep in touch with them, a year later that might yield something much more powerful.

For me, the part of reporting that's the most rewarding and energizing is just hearing directly from people whose voices haven't often been heard, or incorporated into mainstream media. That stuff is really, really gratifying, and so to realize that you could make a career of that part of it, that appealed to me.

When everyone's focused on the conventional parts of war - doing infantry imbeds or chasing IEDs - you look at the thing that seems not that interesting to people, like the circumstances of logistics workers cooking the troops' food or cleaning their latrines.

I learned a lot, investigative methodology - wise, from litigators - watching their process.