Describes behavior or a person lacking manners; often used for breaches of etiquette or social rudeness.
Everyone was surprised by his rude attitude.
食事中に音を立てるのは不作法だ。
Making noise while eating is ill-mannered.
Looking at your phone during a meal is a rude thing to do.
He ended up behaving rudely in front of the customer.
無作法 focuses on a lack of manners or etiquette, while はしたない carries a stronger sense of moral shamefulness or indecency.