The consent form does not go to liability. That is a separate issue. If the tattoo artist's work fell below the standard of care, then he was negligent. You should consult with a personal injury/medical malpractice attorney in your area. Most offer free consultations.
The information you obtain at this site is not, nor is it intended to be, legal advice. The information provided does not form an attorney-client relationship, and should not be relied upon to take or refrain from taking any action.
Your reference to the poor quality of the work, that is more in the realm of a breach of contract claim, in that he did not provide you with the type and/or quality of a tatoo that you paid for. Howevever, the recoverable damages in that instance wouldl only be the amount you paid for the tattoo or the cost to have it redone/improved, which ever is less; and you would need to produce expert testimony - from another tatoo artist, attesting to the poor quality of the work, from a professional standard.
Consult with a personal injury attorney for more details and advice. Many of us offer free consultations. Good luck to you.
I agree with the comments above that there may be a breach of contract claim. Depending on the facts, you may also have a claim for negligence. If you have concerns about whether your potential claims have significant enough of damage to merit bringing a law suit, you should speak to an attorney.
You will need to have a similarly trained artist appear in the courtroom with you. That artist will need to be prepared to talk about the training he/she underwent and why they believe they have the credentials and experience to act as an expert witness in your case. That witness then will need to testify as to what the standard of care is for artists and why he/she believes the defendant artist acted outside that standard. Your witness will need to testify as to what it will cost to repair the work done negligently by the defendant and what the ultimate result will be after such repair work.
I would get the letter you mentioned in your note. There may well be lawyers in your area that would be willing to represent you on a contingent basis. Such lawyers may find that the defendant artist has insurance coverage for such mistakes and the lawyer may be able to work out a settlement with the insurance company rather than going through small claims court.
I hope that helps.
Sign up to receive a 3-part series of useful information and advice about personal injury law.