It is a requirement under Connecticut state law to set the grounds for your divorce in your complaint. The complaint is the document that starts the action before the court. Prior to the advent of the no-fault grounds,which is the marriage breaking down and being irretrievable with no reconciliation possible, there were the fault grounds that were cited. The fault grounds would have to be proven. Fault grounds might include adultery, abuse, intoxication, abandonment, or other causes for the breakdown of the marriage. It remains available for litigants to still use the grounds today.
Using the no-fault grounds does not mean that fault is not relevant in deciding financial issues before the court. Our statutes show that fault may be a factor that a court would consider when making a determination of alimony (deciding whether an award is appropriate in your case), the amount and duration of alimony, or equitable distribution of your property. It is commonplace today that setting forth the no-fault grounds is the choice of most litigants.