The votes collection holds all known votes taken in Congress.
Votes taken by roll call have an ID unique among roll calls:
[chamber code][roll number]-[year]
e.g. "s20-2010" for Senate Roll Call No. 20 from 2010.
There is currently no way to uniquely reference voice votes.
We do not have information on voice votes taken on procedural items; only voice votes that are taken on passage of a bill or resolution. The same applies to "unanimous consent" agreements.
All roll calls, whether procedural or on passage of a bill or resolution, should be present.
There is one exception, which is the vote for Speaker of the House. For this vote, the vote value is either the name of the candidate, or "Present" or "Not Voting".
The only fields you can assume are present on every vote are:
For roll call votes, the following additional fields are always present:
If the "search" parameter is passed to the API, a case-insensitive pattern match of the given string is applied to the following fields:
This is an example roll call vote, House Roll No. 165, from 2010. Some details have been trimmed, but all fields are present which apply to this vote.