There are many from which to choose. One of the most elemental lies in how the Executive Branch can enforce laws, not pass them. It is the legislative branch that is the seat of all legislation starting. Another example of checks and balances can tie into the relationship between the three branches can be seen with justices on the Supreme Court. The President, in the form of the executive branch, can appoint individuals to sit on the Supreme Court. The legislative branch is to confirm these individuals and after confirmation, the members of the Supreme Court can interpret the actions of the Executive Branch and the acts of Congress on the grounds of constitutionality. In this light, one can how essential the principle of checks and balances is to the Constitution.