There are several grounds upon which you may contest a will. Before you decide, you need to ensure that whatever grounds you choose matches up with your evidence.
You must prove to the court that the circumstances you claim were present. If you choose to contest on the grounds of undue influence, the New York City Bar explains that the burden of proof lies on you to show that someone exerted control over your loved one to the point that he or she no longer had free will to create the estate document according to his or her wishes.
Understand undue influence
You should be aware that when proving your case, you must show that your loved one had a diminished mental capacity at the time of creating the estate document or the portion you wish to contest. Undue influence can only occur when the person was not mentally fit.
You also need to show the person applying the influence was someone stronger and in a position to push your loved one to make such decisions. Finally, you have to show that the decisions made were not the wishes of your loved one.
You will often run up against some particularly difficult issues in proving your case. Undue influence is one of the hardest grounds to prove because you probably were not present at the time it happened. In fact, nobody but your loved one the person exerting the influence over him or her was likely present.
However, undue influence often occurs over time. The person may work on your loved one over time to change how he or she feels. There may be various instances where someone else was present and can attest to the manipulating tactics the person used.