Sounds like the two of them may have a referral arrangement. I am unsure hoe California law views this situation. Letters of protection are valid however, and the chiro can take his money from your settlement
In California a lawyer cannot give a medical provider a referral fee or visa versa. If money has changed hands between the lawyer and the chiropractor for the referral then this is unethical and impermissible. But for a Chiropractor to suggest a lawyer with whom he or she has worked with in the past is not 'shady', is very common and is entirely permissible under California's rules of ethics.
A lien can be a good option if you do not have the means to pay for the treatment. Under a lien the attorney will agree to protect the chiropractor's interests when the case concludes and in return the chiropractor agrees to withhold payments until the conclusion. If your chiropractor has referred you to an attorney it is probably because the attorney has a proven track record with the chiropractor of recovering for his/her clients.
Still, if you are not comfortable with your chiropractor you should seek alternative treatment options. You will still be obligated to pay the bill when the case is over, but you certainly do not have to treat with him/her simply because there is a lien. The same is true for your lawyer, you should feel comfortable with him/her and should feel safe to direct these types of questions to him/her.
Oftentimes chiropractors will provide their auto accident patients with the names of two or three reputable personal injury attorneys. They do this because, unfortunately, chiropractors will many times get ripped off by their patients once the case settles. If the patient is not a "cash" patient (i.e. personally pays for each visit) or is not covered by health insurance for chiropractic care, then the doctor will only work on a lien basis so that he/she knows that he/she will be paid when the case settles.
This is not a shady, underhanded or illegal practice unless a referral fee is paid by the lawyer to the chiropractor or if there is some sort of quid pro quo arrangement. Trusted referrals are always welcomed by any professional (doctor, lawyer, CPA) but referrals must be made within the ethical bounds of the professions involved.
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