The sale would probably be enforceable.
The Chatbot is acting as an electronic agent of the car dealer. It doesn't have to be a legal person to do that, any more than an order form of an online business. Most online sales of goods and services are done by electronic agents without human beings in the loop. People routinely by goods on Amazon.com, rent cars, make binding bookings of hotels, get car insurance, open credit card accounts, pay credit cards, buy and sell stocks and bonds, etc. in that way.
You can even buy a car that way and there are firms, like Carvana, that specialize in selling cars online. One of them has a "car vending machine" a couple of miles from my house which is shown below:
Even governmental bodies routinely do business through electronic kiosks and online portals. I file court papers that way instead of dealing with a human clerk, I renew my car registration that way, and I pay some of my taxes that way. I can order a new trash can from the city operated trash department that way.
Australia handles bids for many government contracts that way, for everything from office equipment to oil changes for government fleet vehicles to military submarines. See, e.g. here (the website of a private vendor trying to broker access to this free government service).
This seems modern and novel, as an invention of the 20th and 21st centuries, but is really no more innovative than a vending machine, something that has existed since the Greco-Roman classical era. There is no general prohibition on the use of electronic agents who are not legal entities independent of the entities upon whose behalf they act. The concept of an electronic agent is expressly recognized in federal law at 15 USC § 7006(3), as part of a larger statute the permits businesses and governments to use electronic signatures. 15 U.S.C. § 7001(h) entitled "Electronic agents" provides that, as a matter of federal U.S. law:
A contract or other record relating to a transaction in or affecting
interstate or foreign commerce may not be denied legal effect,
validity, or enforceability solely because its formation, creation, or
delivery involved the action of one or more electronic agents so long
as the action of any such electronic agent is legally attributable to
the person to be bound.
The answer by Katherine to the contrary is incorrect in that regard.
The assertion in that answer that money must change hands for a contract to be binding is likewise incorrect. There must be consideration in a transaction to form a valid contract. But consideration is present here: $1 from the customer, and 1 car from the dealer. A promise to pay something in the future is sufficient. Under the Peppercorn theory of consideration, which is predominant in U.S. law, the courts do not police the adequacy of consideration in a contract, only its existence.
The main legal issue in this case would be whether a Chatbot had "apparent authority" to make the deal, which is a requirement for an agent's actions to bind the agent's principal, whether or not the transaction is electronic. In the absence of a disclaimer to the contrary, it probably does, because online ordering is so common these days that an interaction with an online interface is generally assumed to be providing a valid and enforceable interaction with the customer.
This could easily be prevented with a disclaimer clicked upon by the chatbot user before beginning the chat, stating that "no deal entered into by the Chatbot is valid until signed in writing on paper in the presence of a human being employed by the dealer" for example. The disclaimer would prevent the Chatbot from acquiring apparent authority vis-a-vis the customer.
Another possible way to invalidate the deal with be that it is unconscionable, because it is substantively so unfair and disproportionate that it shouldn't be enforced, and was secured via the allegedly unfair means of "tricking" the Chatbot. But in the case of a large reputable car dealership run by sophisticated college educated business executives, this argument would be an uphill battle in court. Sometimes businesses offer very favorable deals to customers as loss leaders to generate hype and it would have to overcome that presumption that it was acting as a rational business with a marketing motivation in this case.
