No law shall be passed except by bill, and no bill shall be so altered or amended, on its passage through either House, as to change its original purpose.
Pa. Const. art. III, § 1, under Legislation.
Pa. Const. art. III, § 1
Passage of laws
No law shall be passed except by bill, and no bill shall be so altered or amended, on its passage through either House, as to change its original purpose.