legislation_cosponsors: 99-sres-487, L000504

Cosponsors for tracked legislation. Distinguishes original cosponsors (signed on at introduction) from later additions. Linked to congress_members via bioguide_id.

This data as json

bill_id	bioguide_id	full_name	party	state	sponsorship_date	is_original_cosponsor
99-sres-487	L000504	Sen. Lugar, Richard G. [R-IN]	R	IN	1986-09-08	1