Conversation so far:
What was the Taxpayer Protection Pledge?
Taxpayer Protection Pledge is a pledge by lawmakers to oppose increases in marginal income tax rates for individuals and businesses.
When was the Taxpayer Protection Pledge put in place?
Prior to the November 2012 election, the Taxpayer Protection Pledge was signed by 95% of all Republican members of Congress.

Question: Who passed the pledge?
Self-contained rewrite: Who passed the Taxpayer Protection Pledge?