The Shoplifter should claim first. If the Skeptic's card was stolen, he should claim it at the same time with the Shoplifter who stole the Skeptic. If the Ex-Cop checked a player's card, he should out his information at the same time or right after the Shoplifter claims.
Bank Robber duos can claim that one of them stole the other player's card. The person claiming Shoplifter can say whatever role they desire was stolen.
Bank Robber duos can claim that they saw each other as Rookie.
Hostage and Skeptic claims as Bank Robber usually involve the Robber being very passive and doing their best to avoid any suspicion. They also often claim quickly, so the order in which Hostages claim does not mean much unless someone waits until everyone else has already claimed or waits a significantly longer time.
Ex-Cop should usually check bottom cards, as it gives much more information.