No last will and testament is set in stone so long as the testator, or maker of the will, is of sound mind and capable of making his own decisions. At any time, he may decide to completely destroy his will and make a new one or simply make modifications or changes to his existing will by preparing a codicil, which is an addendum to a will. Informal writings that cannot be verified or alterations to an original signed will, however, may be suspect and open to challenge by heirs of the deceased.
In order to challenge the validity of a will, the contesting party must have standing. Generally, this is someone either named in the will or a relative who would have inherited the decedent's property under the laws of the state had there been no will. A non-relative friend or stepchild not mentioned in the will would generally lack standing to file a will contest.
State laws governing execution of wills and codicils also need to be considered. If the state where the decedent died does not recognize a handwritten, or holographic, will that is not witnessed, an unwitnessed codicil will also not be recognized and accepted for probate. Even in a state that recognizes holographic wills, they are much easier to challenge than a will formally signed in the presence of witnesses. A will that has been modified by a striking through of certain provisions and addition of others, with no formal signatures or witnesses, can often be easily challenged by those with standing to object.
Sometimes the contesting party may feel that someone exerted undue influence on the testator, causing him to change his will. A caregiver for an elderly or disabled person, for example, may gain that person's trust to the extent the testator executes a new will or adds a codicil that meets all the required formality required by state law. Depending on the level of influence, an attorney might have no reason to question the transaction. The court may weigh several issues in determining if the testator was coerced into signing the will, including how closely related the contesting party is to the deceased, the relationship that existed between them and the nature of the influence exerted by the individual.
Since a testator of sound mind may change his will at any time, in order for a contest to be successful, sufficient proof must exist to convince the court the changes were not in compliance with the decedent’s wishes or contrary to state law. The party bringing the action should have valid grounds for doing so and not be jealous or angry because of legitimate changes. If the contesting party received gifts and property during the life of the testator that prompted the change, the court may take those facts into consideration. Witnesses to a will’s execution may play an important role in establishing the validity of a will. Some wills also include a no-contest clause that may disinherit a beneficiary who unsuccessfully contests a will. Such clauses may or may not be upheld by state law.