A bill becomes a law by passing both houses of congress by a vote of
more than 50% of the members of each house.

Then it goes to the president's desk, where he can veto it.

In which case, the bill goes back to the chamber in which it
originated.  If it passes both houses by a 2/3 majority this time, it
becomes law without requiring the president's signature.

Two simple questions:

1)  if a bill passes both houses by a 2/3 majority the first time
around, does it still go to the president's desk?  If so, can he still
veto it, thereby forcing it to pass through both houses again at
2/3rds?  Or would a bill that passed both houses the first time by
2/3rd or more become law immediately, without going to the president's
desk, even ceremonially?

2)  When we're talking about 50% and 2/3rds majority, is that ALL the
members of  Congress, or just the ones who are present when the voting
is done?  For example, if it wasn't a very controversial bill and only
20 senators were on the floor that day, could it be passed by a vote
of merely 11?  Same question for the house.

Please cite a reputable website to back up your answers.

Hello gnossie,

The U.S. Constitution states:

"Every Bill which shall have passed the House of Representatives and
the Senate, shall, before it become a Law, be presented to the
President of the United States; If he approve he shall sign it, but if
not he shall return it, with his Objections to that House in which it
shall have originated, who shall enter the Objections at large on
their Journal, and proceed to reconsider it.  If after such
Reconsideration two thirds of that House shall agree to pass the Bill,
it shall be sent, together with the Objections, to the other House, by
which it shall likewise be reconsidered, and if approved by two thirds
of that House, it shall become a Law."

"The United States Constitution" [Article I, Section 7, Clause 2]
United States House of Representatives
http://www.house.gov/Constitution/Constitution.html

The text suggests that "every Bill which shall have been passed" --
regardless of the majority by which it was passed -- shall be
presented to the President, who may sign or return (veto) it.  And
indeed, the Congressional Research Service confirms that the President
may veto a bill, and that a two-thirds vote to override the veto is
required, although "a measure may have passed originally by a large
majority vote in both houses."

"Congressional Overrides of Presidential Vetoes," by Mitchel A.
Sollenberger, Congressional Research Service (Updated April 7, 2004)
[page 2]
United States Senate 
http://www.senate.gov/reference/resources/pdf/98-157.pdf

The same page of that report states:

"Congressional procedure and tradition, not the Constitution, have
determined that a vote of two-thirds of either or both houses of
Congress means a vote of two-thirds of those Members present and
voting (provided there is a quorum) and not, as is the practice in
some states, two-thirds of those elected."

See also:

"U.S. Constitution : Article I -- Annotations p. 24 -- Clause 2.
Approval by the President" [last paragraph: "The two-thirds vote of
each House required to pass a bill over a veto means two-thirds of a
quorum."]
FindLaw
http://caselaw.lp.findlaw.com/data/constitution/article01/24.html

- justaskscott


Search strategy --

Searched on Google for combinations of these terms:

constitution
veto
quorum
"two thirds"
site:gov

Precisely the information I needed.  Thanks.