Break in Dzhokhar Tsarnaev’s trial allows for reflection

Sometimes being a judge means showing some mercy, and US District Judge George O’Toole certainly was merciful delaying the resumption of the trial of Dzhokhar Tsarnaev until April 21, the day after the Boston Marathon, the race that Tsarnaev bombed two years ago.

Ostensibly, the delay was to allow the defense to work out the logistics of lining up the witnesses they will call during the penalty phase, as they try to convince the jury that convicted Tsarnaev on all 30 counts that they should spare his life.

But it was something of a mental health break, too. The jury needed it. The victims and survivors, too. I’m guessing the lawyers on both sides appreciate the reprieve from preparing for daily testimony, even as they’ll doubtless be working straight through.

The pause that O’Toole has afforded also presents an opportunity to reflect on what was not established by the mountain of evidence assembled against Dzhokhar Tsarnaev during the guilt phase of his trial and to question whether it might be raised during the penalty phase.

A Boston cop I know, who was at the finish line when the bombs exploded and who saved lives that day, has a question.

“Who were the FBI agents who interviewed Tamerlan Tsarnaev after the Russians raised questions about him two years before the bombings, and why didn’t they recognize Tamerlan from the photos the FBI released?” he asked.

It’s a good question, one that the prosecution won’t want to ask, one that the defense needs to ask, if it isn’t deemed irrelevant by O’Toole.

The defense has argued all along that Dzhokhar Tsarnaev was steered into the bombing plot by his older, domineering, more-radicalized brother. Tamerlan Tsarnaev, dead almost two years, will be mentioned as often as his little brother in this phase of the trial.

The FBI did some breathtakingly good investigative work in connecting many of the dots leading to the bombings. Finding Dzhokhar Tsarnaev’s discarded backpack, full of incriminating evidence, in a New Bedford landfill, was a textbook case of a grid examination. They’ll study that at the academy for years.

The accumulation of video evidence — from the Tsarnaev brothers on Boylston Street loping up to the bombing sites, to the murder of MIT police Officer Sean Collier, to the escape of carjacking victim Dun Meng, to the shootout on Laurel Street in Watertown — makes this perhaps the most technologically savvy investigation in US history.

The defense was able to poke the FBI in the eye from time to time, pointing out that a few Google searches would have shown some of the words attributed to Dzhokhar Tsarnaev were not incriminating but merely rap lyrics. Still, the evidence assembled by the FBI was overwhelming.

But that nagging question — why wasn’t Tamerlan Tsarnaev identified earlier — won’t go away. And it feeds the nagging sense that the FBI knows far more about Tamerlan Tsarnaev than it’s sharing.

Nor will questions about Tamerlan’s wife, Katherine, go away. The government broadly hinted but never came right out and said they believe the bombs or at least components for the bombs were assembled at the Cambridge apartment Katherine and Tamerlan shared with their daughter, a toddler.

The defense didn’t try to debunk the suggestion nearly as strongly as you might think because it allowed them to point out that the fingerprints on all the tools that might have been used to make the bombs were Tamerlan’s, not Dzhokhar’s.

Why wasn’t Katherine charged? Did she cooperate with investigators?

One of the other nagging questions is whether the Tsarnaev brothers had any accomplices in gathering all the gunpowder from fireworks they used in their bombs. Listening to testimony about how much powder was needed to make the bombs, it seemed like the Tsarnaev brothers would have to be doing nothing else but dismantling fireworks for months.

That sort of black powder is notoriously messy, but there were virtually no traces of it in the places where both brothers lived.

So were the bombs built elsewhere, and did someone else help them?

Because the defense is trying to convince the jury that their client would not have bombed the Boston Marathon without the influence of his older brother, questions about Tamerlan Tsarnaev’s involvement in the 2011 murder of three men in Waltham take on a relevance they didn’t have during the guilt phase.

The defense can argue that Dzhokhar Tsarnaev was afraid of his older brother, a fear that might have been perfectly rational if he knew or suspected that Tamerlan had murdered three men.

One man who could have shed light on all of this is Ibragim Todashev, but he’s dead, shot to death a month after the Marathon bombings by an FBI agent when Todashev allegedly flipped out and attacked the agent after allegedly confessing to helping Tamerlan Tsarnaev in the triple homicide in Waltham.

There is, of course, one other unanswered question, and that is how the victims and survivors of the death and mayhem Dzhokhar Tsarnaev and his brother brought to Boylston Street two years ago will feel about listening to the explanations the defense gives for why he used a bomb to kill and maim innocent people.

As hard as it was to listen to what the bombs did to the bodies of Krystle Campbell, Lingzi Lu, and Martin Richard, as difficult as it was to hear the clinical detail of what bullets did to the face and head of Sean Collier, this could be just as bad.

Judy Clarke, one of Dzhokhar Tsarnaev’s lawyers, told the jury that what her client did was inexcusable. But Clarke’s job now, the job of all of Tsarnaev’s lawyers, is to talk about mitigating factors, to explain why he did the inexcusable.

In a legal sense, mitigating circumstances are facts that show why someone did what they did.

But if you’ve lost a leg or a loved one, that sounds an awful lot like trying to excuse the inexcusable.