The defence team for accused Boston bomber Dzhokhar Tsarnaev has rested its case in the first phase of the trial.
Mr Tsarnaev’s lawyers called just four witnesses before ending their defence, in a case that could see their client face the death penalty.
He has pleaded not guilty to all 30 charges he faces, including one related to the killing of a police officer days after the bombing.
The bombings in 2013 were the deadliest terror attack on US soil since 9/11.
Three people, including an eight-year-old boy, were killed after two pressure cooker bombs packed with nails, ball bearings and other shrapnel detonated in April 2013. More than 260 people were injured, with many losing limbs.
At the start of the trial, lawyers stunned the court by admitting his guilt, but said that he was acting under the influence of his older brother, Tamerlan Tsarnaev, who died in the aftermath.
And on Tuesday, they called witnesses to back up that claim, with the focus on data found on the brothers’ computers.
A digital forensics expert testified that the older brother researched radio transmitters and guns in the weeks before the attack but no such searches were found on the defendant’s.
The defence team’s hope is that he will be spared execution, and the jury will elect instead to put him behind bars for the rest of his life.
The prosecution rested its case on Monday, after calling more than 90 witnesses during 15 days of testimony. Those taking the stand included bombing survivors, who described losing limbs in the attack.
Massachusetts Chief Medical Examiner Henry Nields testified that the youngest victim of the attacks, eight-year-old Martin Richard, received injuries to every part of his body.
The testimony was illustrated by autopsy photos and the child’s bloody, torn clothing.
The prosecution also said Mr Tsarnaev, who emigrated with his family from Chechnya, had extremist views and wanted to hit back at the US in revenge for military action in Muslim countries.
The brothers set off a pair of homemade pressure-cooker bombs at the crowded finish line.
Mr Tsarnaev was found hiding in a boat in the backyard of a house just outside Boston after a huge police manhunt days after the bombings. He was seriously wounded and taken to hospital.
Tamerlan Tsarnaev died earlier during a chaotic confrontation with police when his brother ran him over and dragged his body up to 30 feet down the street.
Closing arguments in the case are expected to be held on 6 April.