美国法律制度的双轨制
Duality
n. The quality or character of being twofold; dichotomy.

The American legal system features a complexity resulting from American federalism. Within the federal structure, each state retains a substantial degree of autonomy. Each has its own constitution, statutes made by its own legislature, and a body of case law created by its own courts. So it can be said that instead of one uniform set of laws America has fifty one --- a set of laws for each of the fifty sates and one for the federation.

Feature
v.tr. To give special attention to; display, publicize, or make prominent.

Complexity
n. The quality or condition of being complex.

Federalism
n. A system of government in which power is divided between a central authority and constituent political units.

Autonomy
n. Self-government with respect to local or internal affairs:

a substantial degree of autonomy: 相当程度的自治权

Federation
n.Abbr. fed. A league or association formed by federating, especially a government or political body established through federal union.

美国法律制度以复杂为特点，而这种复杂性是由美国的联邦制造成的。在联邦构架内，每个州都保持相当程度的自治权。每个州都有自己的宪法、州议会通过的法规、以及州法院产生的一整套判例法。所以可以说美国有51套法律，而不是只有一套统一的法律---50个州各有一套法律，联邦又有一套法律。

A complication resulting from this duality, or multiplicity, is that choice of law questions frequently arise in multistate transactions or occurrences – if a dispute arises out of a series of activities in different states, or between citizens of different states, and the substantive rights at issue are defined differently in these states, the choice of applicable law, which is governed by different choice of law rules of different states, becomes a very complicated question.

Complication
n. The act of complicating.

Complicate
v.tr.intr. To make or become complex or perplexing.

Multiplicity
n. The state of being various or manifold:

multistate
adj. Of, relating to, or involving several states:

occurrence
n. Something that takes place.

Applicable
Adj. That can be applied; appropriate:

The trend toward uniform statutes has tended to reduce this complication, but conflicts of law problems still exist. So, in studying American law, students should be aware that different states may have different substantive laws and different choice of law rules regarding a particular legal situation, resulting in the possibility that the choice of forum may affect the substantive rights of the parties concerned.

Choice of forum also adds to the complexity of litigation in America, because duality is also present in America’s court system. Instead of one unified set of courts, America has fifty one sets, each of which operates independently of the others, and each of which is complete with its own trial and appellate courts.

The state courts are the courts in which disputes are ordinarily heard. Its trial courts include courts of limited jurisdiction and courts of general jurisdiction.

Most states have trial courts of limited jurisdiction. These inferior courts are authorized to hear and determine cases involving a relatively small amount of money or particular subject matters. The name and authority of courts of limited jurisdiction vary from state to state.

All states have courts, usually organized along county lines, for hearing cases of all types, unlimited by subject matter or amount in controversy. Such courts are referred to as the trial courts of general jurisdiction. The court of general jurisdiction is known by different names in different states: in California it is the Superior Court; in New York, it is the Supreme Court; in many states it is the Circuit Court; in other states it is known as the District Court, The County Court, the Court of Common Pleas, and other names. Whatever its name this is the court which hears all cases that are not channeled elsewhere.

Most states permit appeal of the determinations made by courts of limited jurisdiction. In some states, a litigant dissatisfied with the result of the decision by the inferior court may request that the case be retried in the court of general jurisdiction. In some states, the appeal to the court of general jurisdiction is the final appeal and in others, the decision of the general jurisdiction may be reviewed by further appeal.

All states permit appellate review of the decisions of courts of general jurisdiction. Today, the procedure for obtaining appellate review is usually referred to as an appeal. In a few states there is but one appellate court for appeals from the trial courts of general jurisdiction. Such an appellate court is usually known as the Supreme Court of the state, but in some states it is known as the Court of Appeals or by some other name. In other states there are two levels of appellate courts, the intermediate appellate courts (usually known as the courts of appeals) and the supreme court. All types of appeals from the trial courts are taken to the intermediate appellate courts; further review in the state supreme court is taken only at the discretion of the supreme court or upon special request of the intermediate appellate court.

The Federal court system parallels the court systems of the states except that the federal courts are courts of limited subject matter jurisdiction.

The principal trial court of the federal system is the district court. The district courts are organized along territorial lines called districts. Each district comprises a state or apportion of a state.

The federal district courts have jurisdiction over several types of cases. A principal type includes actions between citizens of different states where the amount in controversy exceeds $10,000. This is known as the “diversity jurisdiction” of the federal courts. A second principal type includes actions by individuals “arising under” federal law, known as the “federal question” jurisdiction of the federal courts. A third principal type of federal jurisdiction is actions by or against the Federal Government and its agencies.

Determinations made in the federal district courts are ordinarily appealable to the United States Courts of Appeals, the intermediate appellate courts of the federal system. The Courts of Appeals, formerly known as the Circuit Courts, principally are organized territorially by groups of states known as circuits. There are at present thirteen Courts of Appeals, eleven bearing numbers (First Circuit, Second Circuit, etc.) with the twelfth being the Court of Appeals for the Federal Circuit. Each Circuit Court consists of several judges who ordinarily sit in panels of three for each case.

The highest court in the federal system is of course the Supreme Court of the United States. The Supreme Court has original jurisdiction over a very limited class of cases, chiefly actions between states. Its appellate jurisdiction covers cases originating in the lower federal courts as well as certain types of cases originating in state courts. Potentially, any case originating in a federal district court may be taken to the Supreme Court. Most of such case must be appealed initially to the courts of appeals and may be thereafter taken to the Supreme Court at the latter’s discretion. Of cases originating in state courts, only those presenting questions of federal law may be considered by the Supreme Court.