Sorry for the delay, but I try to be thorough.
Given that it's an attorney, you have the right, under California law, to demand mandatory fee arbitration, through the Santa Clara Bar Association (I assume you're in Santa Clara County). Here is the link.
A fee arbitration is different from a legal malpractice action in that the only issue before the arbiter is the validity or reasonableness of the attorney's charges. In general, you must review all of your bills and dispute each individual line item that you find is either invalid, because you contend that the service was not rendered, or unreasonable, because you contend that the charge is not consitent with what a similarly experienced attorney in similar circumstances would charge for the same service. This link to the State Bar checklist
for fee arbitrators will show you what you need to try to prove.
You can also argue that the entire bill is unreasonable, but it is usually far more useful to argue every line item you dispute, in addition to making the general argument that the attorney accomplished practically nothing in exchange for the charges and that the charges are unconscionable (shockingly unfair) in relation to the amount of tax liability that you are attempting to avoid.
If you want to really
get in the lawyer's face, then you would have to obtain another expert (I don't know if the lawyer you hired is a bona fide tax lawyer who appears before the U.S. Tax Court and Federal District Court), who is willing to testify that your attorney should have known that your chances of defeating the IRS on the specific issues involved is impossible or extremely unlikely.
This would cost you more money, of course, whereas the fee arbitration will be relatively inexpensive. For a $72,000 bill, the fee is 3% ($2,160). If you dispute a smaller portion of the bill, then the fee decreases correspondingly.
You can, of course, sue the attorney for malpractice, complain to the State Bar Disciplinary Commission, or file bankruptcy and thereby avoid the bill entirely. But, the fee arbitration may be the most effective means of dealing with this issue, before trying anything more aggressive.
Hope this helps.
NOTICE: My goal here is to educate others about the law. I am always available to answer your follow-up questions after you click Accept – however, if you do not click Accept, the website gets paid, and I receive nothing. This is true, even if you are on a subscription plan. So please click Accept, so that I will be able to continue to provide this service for others in the future.
And, if you need to contact me again, please put my user id on the title line of your question (“To Socrateaser”), and the system will send me an alert. Thanks!