Labrum - a cover which may be loosely referred to as the upper lip. Mandibles - hard, powerful cutting jaws. Maxillae - 'pincers' which are less powerful than the mandibles. They are used to steady and manipulate the food. Labium - the lower cover, often referred to as the lower lip.
The President, as head of the federal executive branch, is ultimately in charge of enforcing the immigration laws of the United States. In turn, he must make discretionary decisions about whether and when to prosecute immigration law violators through deportation and other sanctions.
In explaining how the content of immigration law was to be found not in federal immigration statutes, but rather in immigration law as it is actually enforced, the Court explained: âA principal feature of the removal system is the broad discretion exercised by immigration officials.