this one in boston and a kind of showdown between the accused marathon bomber and the victims and their families. Pierre thomas tells us what the families saying they saw on the suspect's face.... See More
this one in boston and a kind of showdown between the accused marathon bomber and the victims and their families. Pierre thomas tells us what the families saying they saw on the suspect's face. Reporter: Dzhokhar tsarnaev arrived at federal court under extreme security, with drivers even checking nearby waterways for bombs. He walked into the courtroom in shackles. The left side of his face was swollen and his left forearm was bandaged. He answered not guilty to all charges and blew a kiss to his sister sitting in court. For victims and their families? I didn't see any remorse. He didn't look nervous. He didn't act like he was -- Reporter: The bomber is accused of killing one of the chief's officers. Today, 20 m.I.T. Officers stood outside the courthouse at attention during th entire proceeding. And look at this picture taken minutes before the bombing. Police say this man is dzhokhar tsarnaev. This little boy, martin richard, killed in the blast. And right over here, two brothers, paul and jp norden, both lost a leg. If you had an opportunity to speak to him directly, what would you say? I wouldn't do much talking to him. Their mother liz came to court today. I want to see who changed their lives forever. What struck you about his demeanor? That he was smirking. I don't know. Just that he had a smirk. Reporter: Outside the court today 20 m.I.T. Officers stood at attention. Tsarnaev was accused of trying to kill one of their own. I didn't see the nervous or fear. Reporter: Sister cried as he was led out of the court today. If convicted he potentially faces the death penalty. Thanks pierre thomas reporting in.
This transcript has been automatically generated and may not be 100% accurate.