Definition
A form of co-ownership where each tenant owns an undivided interest in the whole estate, and upon the death of one joint tenant, the survivor(s) own the whole property pursuant to the right of survivorship, and nothing passes to the heirs of the decedent. Joint tenancy is always created by deed or by will, never by intestate succession. In joint tenancy, there must always be two or more grantees or devisees.

Purposes
Joint tenancies served three purposes at common law:

1. The right of survivorship eliminated the risk that upon the death of a co-tenant, heirs who may or may not be responsible would take the land by inheritance;

2. Joint tenancies were used along with the use (the common law predecessor to the modern trust) to avoid the feudal incidents (similar to estate taxes);

3. Joint tenancies were used to protect illegitimate children (wives & legitimate children were protected by dower, intestate succession and marriage agreements while unmarried women and their children received no protection under the common law; unmarried women could not inherit from their mates & illegitimate children could not inherit from their parents or siblings).

Creation
Four unities required at common law:
P Unity of Possession (interests give identical rights of enjoyment)
I Unity of Interest (interests of the same type and duration)
T Unity of Title (interests acquired by the same instrument)
T Unity of Time (interest vest at the same time)

Termination (Severance):
a. Inter vivos conveyance by one joint tenant severs the joint tenancy so that the transferee takes the interest as a tenant in common and not as a joint tenant.

b. Involuntary conveyance can sever a joint tenancy (if creditor executes a lien to satisfy a debt, purchaser becomes a tenant-in-common with the remaining joint tenants.

c. Simultaneous death of the co-tenants (Uniform Simultaneous Death Act) results in equal distribution of the property. The USDA treats the parties as having died as tenants in common (approximately 40 states have adopted the USDA).

d. Mortgages: In a minority of states that follow the "title theory", a mortgage is treated as a transfer of title and causes a severance. In a majority of states that follow the "lien theory", a mortgage is treated as a lien on title, and one joint tenant's execution of a mortgage does not result in a severance unless the mortgage is foreclosed and the property is subsequently sold. If the joint tenant dies before paying off the mortgage, the creditor is out of luck because the surviving joint tenant takes the property without the lien. The only way that the creditor can protect itself is to obtain the signatures of all the joint tenants.

e. Leases: In a majority of states, a lease does not constitute termination of the joint tenancy.

f. Partition: a joint tenancy is destroyed by a suit for partition which is a judicial procedure to end the tenancy when the tenants no longer agree on the management or disposition of the property. Co-tenants have a right to partition enforceable by a court. There are actually three types of partition: a) partition by sale (property is sold at public sale and the proceeds equally distributed to the co-tenants in proportion to the co-tenants' fractional interests); b) partition in kind (physical division when property is similar in nature); c) partition by appraisal (in some states, one co-tenant is permitted to buy out the others at the appraisal price).

Tenancy in Common

Definition
A tenancy in common can be created in a grant or a will or by operation of law (i.e., by construction or by inheritance). Co-tenants each own an undivided, separate and distinct share of the property. A tenant in common does not own the whole property as in a joint tenancy. Each tenant can dispose of its undivided fractional part or any portion of it, either by deed or will. Each tenant has the right to possess and enjoy the whole estate; this is why the only applicable unity is the unity of possession because each tenant is entitled to possession of the whole estate. There is no right of survivorship – upon the death intestate of a tenant in common, the decedent tenant's interest descends to the decedent's heirs.

Termination
a. A tenancy in common can be destroyed by partition.

b. A tenancy in common can be destroyed by merger when each tenant in common transfers its title to one person by purchase or otherwise.

Tenancy by the Entirety

Definition
A form of co-tenancy similar to a joint tenancy based upon the common law concept of unity of husband and wife. Must be a legal marriage. Each spouse owns the whole estate and not a fractional part. Pursuant to the right of survivorship, upon the death of one spouse, the survivor takes the whole estate and the heirs receive nothing.

Five unities required at common law:
P Unity of Person (unity of husband and wife)
P Unity of Possession
I Unity of Interest
T Unity of Title
T Unity of Time

Termination (Severance):
a. Conveyance: at common law, both spouses must join in the conveyance;

b. Death of either spouse;

c. Divorce eliminates the unity of the person, and the tenants become tenants in common;

d. Judgment execution of joint creditor of both husband and white;

e. Partition: neither spouse has a right to have partition and neither has the power to destroy the tenancy without the consent of the other.

f. In 3 states, if one tenant transfers its interest to the other spouse.