"Communal" implies that 7 tribes sinned: Menachot 45a
This is only done if someone acted on the court's error in judgment: Menachot 45a; Keritot 26a
The korban
Who paid for this offering: Menachot 52a
Deducing the laws of this korban to/from the se'ir avodah zarah: Zevachim 40b-41a
Bringing the korban
What time of day to perform the rite of admitting the sin which warranted this offering: Megillah 20b How many judges were needed for leaning on this offering: Sanhedrin 2a; 3b; 13b
What happens if one doesn't perform all of the sprinklings of the blood on the mizbeiach: Zevachim 39a-41b
Placement of parts on the mizbeiach
The kidneys and the yoteret lobe above the liver: Zevachim 41a-b
Beyond the laws
Even when the community sins, Gd still loves them, and this affects the way the Torah describes the burning of parts of the korban on the mizbeiach: Zevachim 41b
If the community sins, the community loses its special sanctity, and this affects the way the Torah describes the sprinkling of the blood of this korban before the parochet: Zevachim 41b