Harm or the threat of harm is the only thing to be considered when determining if a crime is committed. Motive, or reasons for the action, are only considered as secondary. This is why we have so many degrees of the crime of murder. A person who is shot and killed in a robbery is just as dead a person hit by a falling piano. The first is consider one of the most heinous forms of murder, while the other is negligence on the part of a piano mover. Punishment is warranted in both cases, but there is a wide difference between the two. In either case, the morality of killing is not really factor.
The critical factor in both cases is the law's responsibility to protect the public from both armed robbers and incompetent piano movers.
Aren't we discussing whether moral transgressions should be treated as illegal? If so the starting point is a moral issue. All willful killing of one by another is the immorality you apparently present. If we take immorality actions harmful to another then it is illegal because the community agrees that it is immoral to kill in a society.
It may be the threshold for illegality is sufficiently harmful to others to have a probability of harming the society. That is the immorality of an individual or group needs to have the potential for disrupting, causing the collapse or alteration, a society.
That we play with intent and/or extent of harm caused by the act clearly signals the societal concern. It may be, in some societies, a killing of an individual, say a wife for committing adultery, is justified by joint morality considerations as in a society where heredity is the link to power.
Not in my world. But still.
Put that with your negligent piano mover and we join cultural with secular illegalities. There are secular moral codes too which often nearly match those of the more pious which may be used to justify continuing a morality legality parallel. Or the society may set up a purely secular or political secular such as some think was Russian Communism.
Which brings us back to the issue you presented. Almost always something other than logic mixes with legality in a society in fabricating laws. So what is harm and threat of harm but code words for subjective determination of what is a crime. My harm may be other than physical as has been posted by others. So here we are back at eliminating the separation of motive from what act transpired.
So while there is the need for law to accommodate social need to respond to both armed robbers and negligent piano movers we come back to intent as motive setting the bar for whither and extent of punishment. My insertion of lump it has a place there.
Yes, we are discussing discussing whether moral transgressions should be treated as illegal and the answer is maybe. Morality, moral codes, morals are cultural in their details. Moral codes are rules developed to allow people to live in groups. This is why all moral codes have the same basis, which is "Don't kill your friends and don't steal from your friends. After that, it gets kind of fuzzy. Moral codes are not some absolute divination of right and wrong. It simply doesn't work that way. Moral codes define when something maybe right, and when it maybe wrong. The particular act is relevant. The context and circumstances are.
Thy shalt not kill.
Okay got that, but what if a man is strangling my mother? Can I hit him on the head with a club, even though this maybe a fatal injury?
Well, that's different. It's allowed to fracture the skull of a motherchoker.
Moral codes work fine as long as the group remains small and everyone knows everyone else. We run into a problem when our village, town, city, culture, society, yada yada yada, grows so large, this is no longer possible. There is no way for any person to know everybody or everything about a particular person. We have to appoint agents who are given the job of dealing with people who rob or steal from friends. It is their job to collect facts and determine what happened. This is time consuming. If we are to keep order in our giant village, our moral code has to be condensed to cover the more serious problems.
Soon our village is actually made of many villages and it is inevitable to find conflict between moral codes. This is mainly because different cultures have different beliefs about property. Some may think it is proper to kill a thief, while others say this is a great overreaction. As societies increase in population and take in other cultures, the part of the moral code which is handled by the agents becomes more narrowly focused and the legal code becomes a least common denominator of all the different moral codes.
The property thing becomes significant in your question about killing and adulterous wife. Adultery is a crime against property, and falls under the "killing a thief" provisions of the law. When the denominator is lowered, murdering your wife for cheating on you is always one of the first things to go.
In any workable legal system, the first priority is to determine if a crime has been committed.
"Officer, my car has been stolen." After the policeman establishes who I am, and that I do in fact own a car, he will take my word for it, that it is no longer in my possession.
The second priority is to determine who is responsible.
They find my car and apprehend the person driving it. He can't provide proof of ownership, so he is held as a thief.
The third priority is to establish all the facts, so a proper decision can be made.
The thief is put on trial and given a chance to answer the accusation.
The fourth priority is to decide what to do with him.
He is either found guilty or not guilty. Yeah, he did it.
At this point, everything is straight forward. It's all facts based on what happened in the past. Now, we must project into the future. What do we do about a car thief? We must discourage him from this behavior, and thus discourage other car thieves.
We could rerun this whole scenario with, "Officer, my pen has been stolen." Unless my pen was a Princess Grace Mont Blanc(retail price $895), the policeman is likely to say it's my problem and he can't help me.
Here is what it comes down to. Both are immoral acts of theft, but a stolen ballpoint pen is insignificant. It works the same way with other immoral acts. It's always a maybe.