5 p.m.  

There was an abundance of physical evidence discussed at the trial of admitted Boston Marathon bomber Dzhokhar Tsarnaev Wednesday -- and both the prosecution and the defense may have seen their theories of the case bolstered as a result.

At its core, the Tsarnaev trial is about two dueling psychological narratives.

The prosecution depicts Dzhokhar Tsarnaev as a cold-blooded killer, who planned and executed the Boston Marathon bombings alongside his deceased brother Tamerlan.

The defense says Dzhokhar was a follower, pulled into a horrific crime by a domineering sibling.

Cross-examining a fingerprint expert called by the prosecution, the defense used receipts to show that it was Tamerlan who made several key purchases right before the attacks. He bought two backpacks from a Watertown Target, a soldering gun at Home Depot, and additional supplies from State Line guns and ammo in New Hampshire.

The prosecution focused on two gloves found in the car Dzhokhar drove the night MIT police officer Sean Collier was murdered. They were covered in Collier’s blood—and therefore, harmful to the defense’s claim that Tamerlan was Collier’s killer. 

In addition, the issue of explosives loomed large with the prosecution discussing in detail three undetonated devices built by Dzhokhar and Tamerlan. 

According a state trooper who testified for the prosecution, one bomb was shaped like an elbow to prevent it from rolling after it landed—a design he likened to an “improvised grenade.”

The second pipe bomb was straight—and charring on its fuse suggested it had been lit. Also displayed in court: a large Tupperware container formerly packed with two to three pounds of gunpowder—and discovered inside that Mercedes SUV that the Tsarnaevs carjacked.

For its part, the defense focused on ballistics—noting that the Mercedes was struck repeatedly by police gunfire as the Tsarnaevs fled, with some shots striking the passenger’s and driver’s side headrests. Their goal? Perhaps—showing that Djokhar feared for his life when he ran over his brother and fled to Watertown.   

3 p.m.

Court broke for lunch Wednesday after hearing a great deal about fingerprints — specifically, where the government found the Tsarnaev brothers' prints after the Boston Marathon bombings.

The prosecution established that Dzhokhar Tsarnaev's prints were found throughout both their father’s Honda Civic and the Mercedes SUV that the brothers carjacked, as well as objects, including a Ruger 9 millimeter handgun.

But the defense established that receipts for several crucial pre-bombing transactions bore Tamerlan Tsarnaev’s prints —including one from Target for two backpacks and one from State Line Guns and Ammo in New Hampshire.

12:06 p.m.

Jurors in the Boston Marathon bombing trial have been shown two pipe bombs thrown at police by Dzhokhar Tsarnaev and his brother as they tried to flee days after the deadly 2013 attack.

A Massachusetts state trooper described the devices during testimony Wednesday. Tsarnaev faces the possibility of the death penalty for carrying out twin bombings near the finish line with his brother. Three people died and more than 260 others were injured when the two pressure-cooker bombs exploded.

Trooper Robert McCarthy showed the jury two pipe bombs filled with BBs used by the brothers four days after the marathon attacks as they battled with Watertown police.

McCarthy also showed jurors a Tupperware container filled with explosive powder and fuses found in a car stolen by the Tsarnaevs.