To rescind a separation agreement on the ground of overreaching, a plaintiff must demonstrate both overreaching and unfairness but actual fraud need not be shown.
So, it is possible to “take back” a separation agreement but it is not an easy task. The party looking to undo what has already been done must show that the other party secured unfair terms by exploiting a situation through unconscionable conduct. What is considered “unfair” and what is considered “unconscionable” is for the judge to decide. An individual judge’s discretion in making those calls may not be consistent with your own or that of another judge so looking for consistency or clear-cut, easily identifiable parameters will not be possible. The outcome will depend upon the skill of your attorney in presenting the argument and the discretion of your judge in ruling upon the issue.
To vacate a default in a matrimonial action, the defendant must demonstrate a reasonable excuse for the default and the existence of a potentially meritorious defense. So don’t give in to temptation and “take the easy way out” by simply ignoring the process… as many are tempted to do. The problem does not go away if it is ignored; it gets worse. This may seem all too obvious to most but the defaulting party is not some specimen rarely seen. Many defaults are taken every year and reversing the default (“vacating,” as the lawyers say) is a very difficult undertaking which most often fails.
It is simply a losing strategy to default in the first instance thinking that the default can later be vacated if the terms of the initial divorce are more onerous than you would wish. It is not easy (and often not even possible) to take it back and get a “do-over.”