Destroying the evidence

In 1988, for the first time in its history, Mexico's Institutional Revolutionary Party faced a serious electoral challenge. And so they did what corrupt one-party states are apt to do: on election day, with the opposition in the lead, the computer system set up to tally the results shut down - and when it was restarted, it showed the PRI's Carlos Salinas winning with an absolute majority. Facing allegations of a massive electoral fraud, the PRI (with the aid of its friends the PAN) quickly moved to destroy the evidence, and ordered the ballots destroyed before they could be subjected to a manual recount.

Now, it's happening again:

Top electoral officials and judges are feeding doubts about the outcome of Mexico's presidential vote by declining to release details about a recount of 4 million ballots and by moving quickly to destroy all 41 million ballots, legal experts said Friday.

(Emphasis added).

Destroying the ballots is standard practice in democracies, as a way of preserving the secrecy of the vote. For example, New Zealand law, for example, requires that all used ballots, stubs, and polling both material be collected into sealed packets and stored for six months, before being destroyed unopened in the presence of the Clerk of the House of Representatives and the Chief Electoral Officer. However, this does not apply to packet is needed because the result has been challenged, or for a prosecution - or where it "may reasonably be expected to be". The latter certainly applies in Mexico, and you'd expect their law to have a similar provision.

Given the utter lack of transparency by Mexican election officials, this move doesn't look like defending the secrecy of the ballot so much as destroying the evidence...