Article 1, Section 6, Clause 2: Ineligibility Clause
No Senator or Representative shall, during the Time for which he was elected, be appointed to any civil Office under the Authority of the United States, which shall have been created, or the Emoluments whereof shall have been encreased during such time; and no Person holding any Office under the United States, shall be a Member of either House during his Continuance in Office.
This is known as the Ineligibility Clause. It has two effects. First, whenever a federal office is created or its compensation is increased, all members of Congress are prohibited from being appointed to that office until after their own term as a Representative or Senator would have expired. Second, if a member of Congress is to accept any federal office, he must resign from Congress to do so.
Two points should be emphasized. A member of Congress must resign from Congress to accept a federal office regardless of when it was created or its compensation was last increased. Second, resigning from Congress does not make a member of Congress eligible for an office created during his term or whose compensation was increased during his term. He must wait until his term would have expired before he can accept that office.
Congress has occasionally applied what is called the Saxbe fix when a member of Congress is nominated for office and there is strong sentiment in Congress supporting the nomination. If the Congressman would be ineligible due to an increase in compensation for the office in the current term, Congress has occasionally repealed the increase in compensation to allow him to accept the office, and the courts have ruled this permissible. The Congressman must of course still resign from Congress to accept the office.
The purpose of the clause is to prohibit a form of patronage in which the President obtains votes in Congress by dangling the prospect of appointment to a lucrative position in the Administration. Any Congressman accepting such an office must resign from Congress and can no longer “work from within”, so to speak, to further the President’s agenda. This also ensures separation between the legislative and judicial branches. The only overlap is the odd exception of the Vice-President. This differs from practice in most parliamentary systems, where members of the Cabinet are not only often members of the Parliament, but in some systems are actually required to be members of the Parliament.
There remains the question of what constitutes federal office. It is clear that members of Congress are not federal officials. It is also clear that judges are considered federal officials, though not of the executive branch. In fact, most precedents establishing the parameters of the Ineligibility Clause have revolved around appointments to the judiciary. But is (for example) a member of a blue-ribbon commission a federal officer? The criteria used by the courts are that the position must involve lawful delegation of some part of the sovereign powers of the federal government; and it is “continuing”, meaning that it has some duration and ongoing duties. It may at times be vacant, and it continues beyond a single session of Congress. It has some kind of tenure. Any such position is considered a federal office, is subject to the Ineligibility Clause, and its holders are subject to impeachment and removal from office.