How can I use trello to create a banlist/whitelist?

Hi, I've seen multiple games such as Hilton Hotels use trello to have permanent bans of trollers or exploiters, and I was wondering on how I could use trello in my game to remember which players are banned if they rejoin and also to have a list of users on trello that can have admin when they join if they're on the whitelist. I'm not sure how to go about starting.