What would be 5-7 good points to elaborate on if asked to justify why Claudius' actions were not justified in Shakespeare's Hamlet?

Claudius, the antagonist in Shakespeare's tragedy Hamlet, makes many decisions that lead to conflict between himself and other characters. If you are looking to identify specific actions that can contribute to an argument against any justifications for Claudius, you can easily find 6-7 options. 

First is Claudius' fratricide. While some might argue that specific circumstances can justify murder, the poisoning of King Hamlet was conducted solely from a space of a jealousy and power-seeking. 

Second is Claudius' request for Rosencrantz and Guildenstern to spy on Hamlet. His manipulation of two such loyal friends deconstructs Hamlet's ability to trust anyone around him, further contributing to his downward spiral into madness.

Next is Claudius' decision to spy on Ophelia and Hamlet. This decision reinforces the deceit that Claudius relies on to maintain his powerful position. 

After that comes Claudius' soliloquy, in which he confesses to the audience that he regrets his actions. However, he is unwilling to give up the spoils that have been awarded to him from these sins: Gertrude and the throne. As such, the audience can conclude that he is not truly contrite. 

Then, Claudius write orders to have Hamlet assassinated upon his arrival to England. This is a decision he makes out of fear for his own well-being, not for the protection of anyone or anything else. 

Finally, you can use Claudius' manipulation of Laertes' grief for his own purposes. He takes a mourning son and turns him into a weapon, again using others to his own advantage regardless of their state of being.