I ask a friend to watch my bike while I go shopping, and the bike gets stolen. I can sue my friend for damages but only if I can prove that my friend was:

grossly negligent, or failed to exercise at least slight care, or failed to exercise reasonable care. Which one would be the best answer, if this is all the details of the situation.

Well, since I can't remember the answer from the Bar Exam, let's use the process of elimination.

"Slight care" is not a legal standard under any circumstances, so that's not the answer. Cancel out "slight care."

The first question to ask to resolve this question is what "duty of care," if any, did the friend from whom the bike was stolen owe to the friend who was the owner of the bike. Common law assigns a "duty of care" based on the relationship between the people, e.g. as between a hotel owner and a hotel guest, or a storage company and the person storing his goods there.

"duty of care n.: a requirement that a person act toward others and the public with watchfulness, attention, caution and prudence that a reasonable person in the circumstances would. If a person's actions do not meet this standard of care, then the acts are considered negligent, and any damages resulting may be claimed in a lawsuit for negligence.

Here we have a bailor/bailee relationship between the boy who asked someone to hold the bike (the "bailor") and the friend who held the bike (the "bailee").

"When a bailor receives the sole benefit from the bailment, the bailee has a lesser duty to care for the property and is financially responsible only if he or she has been grossly negligent or has acted in bad faith in taking care of the property. FreeDictionary

The fact that you're not PAYING your friend to watch your bike, and your friend did not ask to borrow your bike would both be reasons for a court not to require him to exercise that much care.

Based on the information provided, the best possible answer would be: "failed to exercise reasonable care."

To understand why, let's break down the definitions of the different levels of negligence mentioned:

1. Gross negligence: Gross negligence refers to a severe lack of care or a conscious and voluntary disregard for the safety of others. It usually involves an extreme departure from what a reasonable person would do. In this situation, there is no indication that your friend exhibited such a high level of negligence or intentional disregard for the security of your bike.

2. Slight care: Slight care typically implies taking minimal precautions or acting with some care, but not necessarily enough to meet the standard of reasonable care. Again, based on the limited information provided, there is no evidence to suggest that your friend only exercised slight care.

3. Reasonable care: Reasonable care is the standard expectation for an individual to act as an average and prudent person would in similar circumstances. It involves taking precautions to protect the property and avoid foreseeable harm. In this situation, if you can prove that your friend did not take reasonable care to safeguard your bike, such as not properly locking it or leaving it vulnerable to theft, you may have a case for claiming damages.

Remember, to ultimately determine the best answer, it is advised to consult a legal professional who can carefully review the specific details of the situation and offer appropriate legal advice.