A sentencing hearing is the last stop before a convicted criminal is sent to jail for his or her punishment. One of the purposes of jail is to punish those that do not respect the systems that we have in place to maintain an orderly society. If, at the sentencing, a criminal curses at a Judge it is clear that they do not respect the system and accordingly that along should net them some additional time in jail.
Disrespect is never ok, especially in a situation where you are in the wrong. If a member of the court, especially the judge is simply doing their job, they should not have to put up with despicable behavior. Cursing out a judge shows that you have no respect and no remorse for your actions. If that's the case, you should be subject to a harsher sentence.
One of the most glaring problems within the criminal justice system is the lack of respect on both sides. The only way for a successful democracy to work is for the public to respect those in authority positions and vice versa. Without respect shown to the other party, the balance is lost. In order to maintain this balance, acts of disrespect need to be addressed swiftly and based on the degree of disrespectful action. When disrespectful acts towards authorities are ignored or minimized, the act becomes acceptable. This act is then built upon until a simple act of disrespect turns into harmful behavior.
No, cursing at a Judge during a sentencing should not net a criminal even more jail time because they are simply caught up in the moment. Being rude should not lead to jail time. It should simply being a stepping stone toward maturity. The criminal should serve the original time he was dealt.