Here's the nut grafs from the intro piece:
The Times’s examination reveals that Wal-Mart de Mexico was not the reluctant victim of a corrupt culture that insisted on bribes as the cost of doing business. Nor did it pay bribes merely to speed up routine approvals. Rather, Wal-Mart de Mexico was an aggressive and creative corrupter, offering large payoffs to get what the law otherwise prohibited.How much, how bad?
We're not talking a few thousand dollars. Nor a few tens of thousands.
Just a little ways into the story, if you're adding the bribe amounts mentioned, you already roll the money odometer past the million-dollar mark.
There's also a culture of corruption. Walmart allegedly never paid bribe money itself, directly, to elected or appointed government officials. Instead, it used a group of ... well, fixers! And ones apparently known to be good at their work. Which then leads one to wonder just how much Walmart knew about them, in terms of advance research.
Anyway, the article is long, but good.