Thanks for the correction, Joe. I thought FERS was a replacement for (like the railrod workers' plan), not in addition to SS.

Most executive level jobs have some sort of retirement plan partially paid for by the same folks who pay their salaries. When it come to Congress, if the taxpayers are going to pay Congressmen and other federal employees a salary, I don't think it's unreasonable that part of their pension plan and the cost of administering it is funded by taxes.

However, I think that having Congress vote on their own salaries and benefits is pretty dumb!

I found this FAQ
on the subject with more raw data.