Last week, I wrote about Casey Johnson, the great-great granddaughter of the founder of Johnson & Johnson (JNJ).  Among your insightful responses was this one, from a reader who’s a Financial Advisor in the Northwestern Mutual Financial Network.

“If Casey Johnson was single at the time of her death–and I think she was–and with no current federal estate tax in 2010, she may well be the first famous “name” to entirely escape federal death taxes. (Her estate would still be exposed to state of California inheritance or California estate taxes).

“And while Congress will supposedly resurrect the federal estate tax retroactive back to 1/1/10, there are any number of constitutional challenges to making a tax retroactive to a deceased person who passed away under then-current tax law.

“Moreover, for very affluent couples with assets exceeding the old 2009 exemption amounts of $3.5MM per spouse if the assets were individually titled, when the first spouse dies, any excess over and above the exemption amount ($3.5MM in 2009) automatically flows into trust bypassing the surviving spouse.

“This has a potentially disastrous effect on the countless wills written across the country that mandate estate asset transfers in this manner.

“Even if the old $3.5MM estate exemption amounts are revived shortly in 2010 by Congress and made retroactive, it will still be too late for millions of assets which passed under will to trusts under the current (no exemption amount due to no estate taxation) tax law for people who died (the already dead) in January 2010.

“Talk about the law of unintended consequences … stunning consequences, simply because Congress couldn’t get their act together on this expiring estate tax law–all of course due to their almost complete and utter fixation on healthcare.”