There's a common misconception that "no-fault" divorce means fault is totally irrelevant - as if one spouse can have an affair and the affair means nothing because the divorce is "no fault." That is incorrect. "No-fault" means neither party needs to prove the other party is at fault for the breakdown in the marriage, e.g. with a string of e-mails that chronicle a sordid affair, to obtain a divorce. "No fault" does not mean fault is totally irrelevant to the divorce.
In many states, like Michigan, fault is relevant to spousal support, property and child custody awards. There is a great variety among states because each has its own body of common law (the prior court opinions that may apply to the case) and its own statutes (the law "on the books" from the legislature). However, with the rise of "no fault" divorce statutes in the 1970s, a general trend emerged that fault could be an issue but not "the" issue for divorce. What was once a fault-focused case now became a case focused on fault only as it affected property, the need for or ability to pay support, and child custody.
In Michigan, the trial court has the discretion to award spousal support, but the award "must be based on what is just and reasonable under the circumstances of the case." The award, if any, must balance the income and needs of the soon-to-be exes without impoverishing either. In other words, the trial court should not award spousal support if, after considering the parties' income, ability to work, health, fault, need, marriage length, age, and any other relevant fact, neither needs it, neither can afford it or the circumstances do not justify it. The tcourt will not be reversed on appeal absent an abuse of discretion.
Underlying spousal support awards at divorce is the partnership theory of marriage. Marriage is a joint venture between husband and wife, and they rely upon each other to work, raise children and maintain a standard of living. That is why the statute authorizing an award of spousal support, MCL 552.23(1), emphasizes the parties' needs and abilities to pay and their character and situation. The statute has not been revised in more than 100 years, and so we are left with a somewhat archaic caselaw featuring homemaker wives and breadwinner husbands. The more recent caselaw, however, features working spouses burdened with debt and unable to support each other at divorce. In that caselaw, the length of the marriage is often the linchpin to determining a spouse's entitlement to support after divorce. This factor shows the interdependence of the other factors because the length of the marriage usually affects the parties' respective property rights, work history and employment potential. In Zecchin v Zecchin, for example, the Court of Appeals approved a trial court's award for permanent support in favor of a wife of a 27 year marriage whose husband had convinced her to take herself out of the job market to live as a homemaker. The consensus is, support is appropriate when the parties share a long marriage and one party did not maintain a career.
Fault would be important if it perpetuated that lifestyle. In other words, if one spouse made the other be a homemaker so he (or she) could maintain an affair at work, the judge might admonish the cheating spouse and award the homemaker spouse rehabilitative support to gain skills and seek employment. A few extra dollars for the affair would be a slap on the hand, and it would cost the cheating spouse more to appeal the decision that it would to pay the extra support. However, if both spouses worked and one cheated but the other's lifestyle was unaffected, then support would be inappropriate because the fault did not affect the spouse's lifestyle.
The problem is, in Michigan judges have so much discretion that virtually any award is acceptable on appeal. A discretionary ruling receives the greatest amount of deference on appeal. Moreover, although the judge must state findings of fact on each support factor, there are so many factors that it is easy to mask what is really punishment for being the faulty spouse by something else - say, a mix of the other's needs and lifestyle. The trial court cannot give "an inordinate amount of weight" to fault, but so long as the trial court rationalizes its decision with the other factors (age, health, lifestyle, employability, length of the marriage, etc), the award will not be set aside on appeal.
So, how do we deal with fault in Michigan?
If I am representing the spouse seeking support - that includes men, because men, although traditionally not the support recipient, can need support just as much as women - I identify the fault in the marriage and then argue at length how it affected my client's finances and lifestyle. This takes guts, because fault is not a popular topic, and it takes an attorney not afraid to advance the arguments. I investigate each way fault is linked to money or property. For example, if my client tells me his wife has a gambling habit and that habit caused the couple financial ruin and their marriage to deteriorate, I want: witnesses to tell me how often she gambles; photographs of her gambling; bank account records showing her withdrawals and deposits for gambling; deposition testimony from the crowd she frequents; copies of unpaid bills; a spreadsheet showing how much money the couple would have saved had she not gambled; etc. I want all of these items in court, on exhibit boards or a PowePoint presentation, so that I can show the judge how a gambling habit has caused financial problems and how much that spouse would have to pay support if she stopped gambling. Similarly, for a cheating spouse courting her new beau, I want bank account records showing trips, gifts, bills for fine dinning, etc., photographs of dates, deposition testimony from witnesses, etc., to prove that the cheating spouse led a secret, higher standard of living and, therefore, has money to elevate my client to a higher standard of living.
If I am representing the at-fault spouse, on the other hand, I divert attention from fault and restore it to where it ought to be: needs and ability to pay. Those are the two most important factors. I subpoena bank, school and employment records, interview fellow employees, take pictures of the couple's home, and otherwise gather evidence to prove that the spouse seeking support is employed, employable and living a decent standard of living, irrespective of an alleged affair. I have my client prepare a monthly budget with basic expenses --- food, transportation, housing - to show he simply has no money to pay support. Again, I put these things on exhibit board or in a PowerPoint presentation to show that the couple's standard of living will be about equal.
In my last spousal support trial, in fact, I got the wife to admit, happily, that she is "a great worker," has "a great job" and "had been employed for the entire marriage" - even during the time that, she claimed, my client was having an affair. The judge interrupted her and said, "Then why do you need support?" I sat down and said, "No further questions, Your Honor."
The key is to use fault when it suits your case and minimize it when it does not. That means knowing the judge, too. It's up to the judge to decide how much support the at-fault spouse pays, and a well-prepared case could make that spouse the cheater who spent away his wife's lifestyle (and so should pay support) or the love-lost guy with no money whose marriage fell apart (and so should not pay support). That decision, unless wholly outside the realm of reason, will withstand an appeal.
 Moore v Moore, 242 Mich App 652; 619 NW2d 723 (2000).
 Magee v Magee, 218 Mich App 158; 553 NW2d 363 (1996).
 149 Mich App 723; 386 NW2d 652 (1986).
 See, e.g., Johnson v Johnson, 346 Mich 418; 78 NW2d 216 (1956) (20 yearmarriage); Demman v Demman, 195 Mich App 109; 489 NW2d 161 (1992) (23 year marriage); Ross v Ross, 24 Mich App 19; 179 NW2d 703 (1970) (14 year marriage).
 Welling v Welling, 233 Mich App 708; 592 NW2d 822 (1999).