Oregon ballot measures have this basic format (this particular one is an initiative for a constitutional amendment, but referendums [referenda?] are similar, as are measures for regular legislation):
Whereas, ABC is good and XYZ is bad, and
Whereas, the state government currently promotes XYZ rather than ABC, and
Whereas, the state government should promote good things,
Be it enacted by the people of the State of Oregon,
Article 1, Section 1 of the Oregon Constitution is amended to read,
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What is the "whereas" part called?