Menem, you may recall, introduced Chilean-style private pension schemes (known as AFJPs) in 1994 on the advice of the World Bank and IMF.
Though initially popular, AFJP accounts were subject to exorbitant commissions - at least 30% of total monthly contributions, and as high as 54%.
The AFJPs, moreover, were often fraudulently run (more on that below). They also suffered huge losses during the 1998-2002 crisis, such that by 2008 the state subsidized 77% of the funds' beneficiaries, including 40% whose annuities could not cover minimum monthly pensions, at a cost of $3 billion in taxpayer money annually.
Chile's experience has been similar (so much for "private" ). Their copper earnings, however, are more than enough to cover their pension commission problem - a facility Argentina doesn't really have.
Following Boudou's advice, in October 2008 Cristina Kirchner nationalized private pensions. These accounts were transferred to the ANSES social security agency, while leaving contributors the freedom to invest in private pension funds (not many did).
As you can imagine, the banks were pissed. They had been accustomed to using the AFJPs as dumpsters for their bad stock picks, since the AFJP managers would often buy falling stocks without too many questions (often in return for a bribe).
Once this scam was curtailed by nationalizing the AFJPs, they vowed revenge - and attempted to bankrupt the newly nationalized funds (which were heavily invested in stocks) by triggering a panic.
Boudou's steady hand as ANSES director at the time forced them to relent, causing stock prices to spring back and thus saving the funds.
Of course, he's certainly not the only former Kirchner official to have been jailed on trumped-up charges (or sometimes, no charge at all).
A few have been properly convicted, with evidence, on corruption charges (as they should be); but they are very much the exception - to say nothing of the fact that Macri and several in his cabinet and inner business/family circle would be as well if the judiciary functioned properly.
"There is nothing to celebrate," Boudou noted after being freed. "We must endeavor to have no political prisoners in Argentina because our democracy can't allow it."