A properly drafted and executed will allows you to do two things: (1) specify who should receive your property after your death; and (2) appoint a person to act on your behalf to distribute your property according to your wishes. If you pass away without a will, you are said to have died “intestate,” and the laws of intestacy are substituted for your judgment with respect to these matters.
The Laws of Intestacy
The laws of intestacy vary from state to state, but in general, the goal of intestacy is to distribute your estate in accordance with what most individuals would want. In New York, for example, the laws presume that you most likely would have left your property to your spouse and children. So, if you are survived by a spouse and no children, your entire estate goes to your spouse. If you are survived by a spouse and children, $50,000 plus ½ of your estate goes to your spouse and the remainder (if any) is divided equally among your children. The laws continue to branch outward, each time embracing more distant heirs such as grandparents, siblings, aunts, uncles, cousins, and first cousins once removed.
The laws of intestacy also determine who will act to distribute your property on your behalf. This individual is called the “executor” if appointed by a will or the “administrator” if appointed by intestacy. The executor/administrator fulfills a very important role because he or she is ultimately responsible for ensuring that your estate is properly distributed. The executor/administrator will have the authority to access your bank accounts and other assets for this purpose.
If you create a will, you can name almost anyone to serve as executor. On the other hand, if you let intestacy govern, the law will make this determination on your behalf. The laws specifying who can be named as the administrator try to approximate what most individuals would want. For example, in New York, if you are survived by a spouse, your spouse has priority (assuming your spouse is not an infant, incompetent or a felon). If you are not survived by a spouse, your children have priority, followed by your grandchildren, and finally by other remote heirs.
Although these laws are a good start, they might not suit your specific circumstances. For example, you might not want your spouse to inherit your estate if you are separated but not yet divorced. You might not want your children to inherit their portion of your estate outright, particularly if they are very young or if the inheritance will disqualify them from receiving government benefits. You might want to disinherit certain heirs entirely. You might want to leave something for a close friend or domestic partner. You might want to leave specific items to specific individuals. Your children might be better suited to serve as executor than your spouse. Intestacy does not allow for any of these contingencies.
If you pass away without a will, the laws of intestacy determine how your estate is distributed and who has the authority to distribute it. Although intestacy attempts to approximate a distribution that is acceptable to most people, it may not suit your specific needs. If the laws of intestacy do not match your specific circumstances, you should consider creating a will that will govern the distribution of your estate.
 See N.Y. Est. Powers & Trusts Law § 4-1.1 (note that this is the law in New York as of the time of writing this entry; laws vary state to state).
 See N.Y. Surr. Ct. Pro. Act §§ 1001 and 707.