But it wasn't until Sunday that Souder told him the affair was with a staffer.
Pence spokesman Matt Lloyd described the timeline in a statement: "In response to a general media inquiry, Mr. Pence confronted Mr. Souder on Thursday. Mr. Souder confessed to an affair, but did not mention that it was with a part-time staff member. It was not until Sunday evening that Mr. Souder called Mr. Pence to inform him that the affair was with a part-time staff member. Mr. Pence encouraged Mr. Souder to resign immediately and notified ethics on Monday."
Pence wasn't the only Republican leader who went to the ethics panel. After a conversation with Souder Monday, Minority Leader John Boehner "sent a letter to the House ethics committee informing the panel of his conversation with Souder," Politico reported.
Souder himself said Tuesday that if he did not resign, "any legal question would have been clearly resolved and I would have been exonerated."