Task: Categorize the tweet's emotional expression, classifying it as either 'neutral or no emotion' or as one or more of the specified emotions (anger, anticipation, disgust, fear, joy, love, optimism, pessimism, sadness, surprise, trust) that reflect the tweeter's state of mind.
Tweet: As I remember and reflect on Reginald Denny on a night much like this (like #Charlotte) I think to myself, the gun lobby must be rejoicing.
This tweet contains emotions: 
joy