The common law still plays an important role in criminal law, even though most of today`s crimes are enshrined in law. The classification of crimes as felonies reflects English common law. Legislators often create laws out of old common law crimes. Judges follow the common law when defining legal terms, initiating criminal prosecutions and creating defences for crimes. The United States is considered a common law country. All states, with the exception of Louisiana, which is based on the French Civil Code, adopt common law as state law, unless a law provides otherwise (Legal Definition, 2010). Many complex rules govern the use of precedents. Lawyers mainly use precedents in their arguments, not laws or the Constitution, because they are very specific. With proper research, lawyers can usually find precedents that match or are very close to the facts of a particular case. In the broadest sense, judges tend to follow more recent precedents, coming from a Supreme Court and the same judicial system, whether at the federal or state level. Regulations are created by federal, state, and local legislators, who are composed of elected officials who have the power to legislate. Courts must, where available, apply laws to the facts of a case. If there is no law, the courts refer to the common law or case law.
Common law refers to laws that have not actually been codified or enacted by a legislature, but are nevertheless applied by the courts according to the legal tradition and history of the United States, and even trace back to the legal system in England. Case law refers to law that flows directly from court decisions. „Jurisprudence“ consists primarily of judicial interpretations of the Constitution, statute or common law. „Jurisprudence“ includes decisions of the Supreme Court and lower courts. Because laws are passed by legislators who have the power to legislate, statutes govern common law or jurisprudence when the two are in conflict. An exception is that a law may be repealed by a court if the law is unconstitutional (inconsistent with the constitution) as interpreted by the applicable case law. The second source of law is legal law. While the Constitution applies to state action, laws apply and regulate individual or private action.
A law is a written (and published) law that can be enacted in two ways. Most laws are drafted and passed by the legislature. It is simply a group of people elected for that purpose. The U.S. legislature is called Congress, and Congress passes federal legislation. Each state also has a legislature, called the state legislature, and a state legislature votes on state laws. States often codify their criminal laws in a penal code. For security reasons, we see more exceptions to constitutional protections in public schools and prisons.
For example, public schools and prisons may prescribe a certain style of dress to ensure safety. Technically, forcing a person to dress a certain way could violate the right to self-expression guaranteed by the First Amendment. However, while wearing a uniform can reduce gang conflict at school and prevent prisoners from escaping, the government can constitutionally suppress free speech in these places. Read Keeler v. Superior Court, 470 p.2d 617 (1970). In the Keeler case, the accused attacked his pregnant ex-wife, and their baby was subsequently stillborn. The California Supreme Court dismissed a murder charge against Keeler under Section 187 of the California Penal Code because the law only criminalized the malicious murder of a „human being.“ The court made its decision after reviewing the human definition and concluding that the definition did not include the fetus. The court argued that he could not create a new crime without violating the Due Process Clause, the separation of powers, and Section 6 of the California Penal Code, which prohibits the creation of common crimes.
Following the Keeler decision, California legislators amended section 187 of the Criminal Code to admit a fetus, except for abortions (Cal. Penal Code, 2010). The U.S. legal system is adversarial and rests on the premise that a genuine and living dispute, involving parties who have a genuine interest in its outcome, allows for the most vigorous legal debate on issues, and that courts should not have the power to make decisions unless they respond to genuine controversy. Therefore, federal courts are prohibited from issuing „advisory“ opinions or opinions that do not relate to an ongoing case or controversy. (These principles are based on Article III of the U.S. Constitution, which limits the jurisdiction of the Federal Court to „cases and controversies.“ Unlike federal courts, some states allow cases that are not based on actual controversies to be brought and therefore do not share the federal court`s bias against expert opinion.) Civil law systems rely less on precedents than on codes that explicitly provide rules for many specific disputes. If a judge has to go beyond the letter of a code to resolve a dispute, his or her decision will not become binding or even relevant in subsequent decisions involving other parties.