Section 2A:34-2 of the New Jersey Divorce Statutes outlines the different causes of action available for a divorce. The fault grounds include adultery, desertion, extreme cruelty, voluntary addiction or habituation, institutionalization, imprisonment and deviant sexual conduct. Desertion must be willful and continued for a period of 12 months or more. Extreme cruelty can be mental or physical but must be to the extent that it makes it unreasonable to expect the parties to continue to reside together. The fault ground for voluntary addiction refers to addiction to any narcotic drug and/or habitual drunkenness for 12 months or more. Institutionalization for a mental illness must be of a period greater than 24 consecutive months. Finally, deviant sexual conduct is that which is voluntarily performed by the defendant against plaintiff's will.
New Jersey also recognizes no-fault grounds for divorce on the basis of separation or irreconcilable differences. The parties must live separately for at least 18 consecutive months with no prospect of reconciliation to succeed on the no-fault ground for separation. The parties may have experience irreconcilable differences for six months or more to succeed on that ground. All grounds for divorce require NJ residency for a period of at least one year with the exception of adultery. An adultery claim requires the third party who participated in the adultery be named as a co-defendant.