You're a trial judge in a state court hearing a divorce case. There's no jury, just you. The two parties both agree to a divorce, so that's off the table. The question is how to divide up the property. Assume the general rule for the state you live in is that both parties are entitled to keep what property they brought into the marriage, and that property generated within the marriage is split between the two on divorce (meaning, for instance, that if the husband gets the physical house, he has to pay the wife half the value of the house, and this goes all the way down the line until we get a final accounting at the end).
The facts of this case are interesting, and this matter has never come before a court in your state before. The husband and wife married towards the end of their respective college careers. He was a year away from a bachelor's degree in Biology, she had just finished her degree and had been hired as a student teacher. He planned on going to med school; she wanted to get her teaching credential. Both would have required more school, meaning no income (and significant expense). After talking it over, the couple decided that she would work full-time and support the two of them, while he went to school. A year later they moved to Florida, where he went to med school. After 3 1/2 years, they moved to your state, where he's doing his internship and residency. The entire time she moved along with him and provided his financial support. She paid all of the couple's living expenses and most of his tuition bills (the rest was paid with help from his family and some small student loans). After years of hard work he finished his training and got a board certification for a fairly lucrative surgical specialty. Two months later he filed for divorce.
This couple is quite poor. For the last seven years, every cent has been going to basic living expenses and tuition payments. They obviously have furniture and some simple property, but they're not disputing over that. They rent, so there's no real estate to divide up. The wife has made a novel argument, which is the entire dispute in the case: the husband's degree and professional certification should be accounted as marital property, a capital investment jointly made by wife and husband, and as such she owns a share in it. Therefore, she should get something in the way of maintenance for all the money and work she invested in the degree.
The husband, naturally, disagrees. A professional certification is not marital property, because it isn't property at all. It's an official recognition of educational achievement. It doesn't have any of the standard features of property. It's not alienable (he can't give it to someone else). It has no market value (he can't sell it). It's not a physical thing. He can't divide it in half. He can't will it to an heir. It ceases to exist upon his death. All it is is an opinion by a board somewhere. How can it be property?
So, several questions for you: First, is it property? And is it marital property, jointly owned by husband and wife? If not, should the husband nonetheless be compelled to reimburse the wife for what she paid into the marriage? If so, how do you decide what the wife should get? Should it be the value of what she put in? The expected future value of the license? And what percentage is she entitled to? She paid more than half of the money that went into it, but isn't there also the element of the husband's work and endeavors to earn the degree?
Assume that there are no extenuating circumstances like abuse or infidelity that would cause the court to be biased toward one party or the other. Further, make your judgment according to what you feel the law should be, not what you think the law is. For one, since divorce is handled at the state level there are actually three major schools of thought on property in a marriage, and each state has its own kinks and peculiarities. Further, this very issue has been decided in radically different ways in different states, so it's a question that's open to dispute.
Generally, though, assume your state has de jure sex equality in its marital property laws (the wife isn't the property of the husband at marriage) and that, as described above, the system is that property brought into the marriage belongs to the one what brought it, and that property generated within the marriage is jointly held.
I would have him pay her back for the cost of his education, and half of their living expenses during the duration of the marriage and end it at that.
She paid for his certification, and now that they are separating, he owes her for that and all the other expenses it took to live.
I know I said end it at that, but I feel wishy-washy about that. If we considered it property, I compare it to a show car. Say they bought it together in need of great repair. It has the potential for greatness, but not guaranteed. He pays her for it, turns it into the most famous car ever, and sells it for a huge profit. He doesn't owe her part of the profit, since he took advantage of the opportunity, she didn't do anything to make it profit-worthy. (Substitute a remodeled house if thats easier to understand). I don't know. I need to work on my written reasoning if I ever want to go to law school!