A constitutional lawyer is an attorney who tries cases where constitutional issues are at stake. The Constitution is considered the Supreme Law of the United States, and is a form of federal law. Thus, most cases based on constitutional questions are tried in the federal court system.
Like any other law, the Constitution imposes certain mandates for behavior. The Constitution primarily imposes behavioral mandates on legislatures and courts and other law making bodies. The Constitution dictates that any law that is made must not violate a person's constitutional rights.
When a person believes his constitutional rights are being violated by a law, that person can raise a constitutional question. He can sue the law making party for the violation of his rights. If he believes some other entity is violating his constitutional rights, he can also sue that entity.
A constitutional lawyer will then represent the person who believes his constitutional rights are being violated. The constitutional lawyer will file suit in federal court on behalf of the person whose rights are violated. The cause of action will be based upon the rights set forth in the Constitution.
Each state has its own Constitution, and states are bound to uphold not only the federal constitution, but the state constitution as well. If a cause of action arises out of state law, the case will be brought in state court instead of federal court. In this situation, a lawyer who is an expert in the state constitution will be called upon to represent the plaintiff.
Regardless of whether the case is based on the federal constitution or the state constitution, a constitutional lawyer will need to prove that his client's constitutional rights are being violated. This can involve arguments regarding how various provisions of the constitution should be interpreted. It can also involve showing evidence as to how those rights were violated.
Many famous cases are based upon rights set forth in the constitution. For example, Roe versus Wade, the famous abortion case, is based on the Constitutional rights to due process of the law and to privacy. A constitutional lawyer argued this case on behalf of a woman who believed that denial of the right to an abortion constituted denial of her right to freedom, as set forth in the constitution.
Constitutional lawyers often argue groundbreaking cases that reach the Supreme Court. Lawyers must be well versed in legal interpretation, and must be able to support their legal arguments with references not just to the constitution, but also to past interpretations. Many lawyers who work on cases of constitutional importance work for legal aid organizations, or work on a not-for-profit basis to defend what are believed to be the nation's fundamental rights and freedoms.