Peccant, ( \PEK-unt\ ), adjective

1 :guilty of a moral offense : sinning 
2 :violating a principle or rule : faulty  

Examples: Outside the confessional stood a short line of peccant parishioners waiting to seek redemption for their sins. 

“His own translation of Heinrich Heine’s ‘A Woman’ features a naughtily misbehaving protagonist and herpeccant boyfriend….” — From a review by Benjamin Ivry in The Forward, April 27, 2012  

Sponsored Link    “Peccant” comes from the Latin verb “peccare,” which means “to sin,” “to commit a fault,” or “to stumble,” and is related to the better-known English word “peccadillo” (“a slight offense”). Etymologists have suggested that “peccare” might be related to Latin “ped-” or “pes,” meaning “foot,” by way of an unattested adjective, “peccus,” which may have been used to mean “having an injured foot” or “stumbling. “Whether or not a connection truly exists between “peccant” and “peccus,” “peccant” itself involves stumbling of a figurative kind—making errors, for example, or falling stumbling.” Whether or not a connection truly exists between “peccant” and “peccus,” “peccant” itself involves stumbling of a figurative kind—making errors, for example, or falling into immoral, corrupt, or sinful behavior.