Boston Mayor Calls Marathon Bombing Trial Painful But Necessary

— -- On the eve of jury selection, Boston Mayor Marty Walsh said the trial of surviving marathon bombing suspect Dzhokhar Tsarnaev is painful but necessary.

The blasts killed three and injured more than 260 and for those families the trial, which is expected to last for months, "is going to be a tough time," since "a lot of families are going to relive what happened on that horrific day," Walsh said.

But Walsh said "the judicial process has to take place" if survivors and families of victims are to ever have the chance to move on.

The mayor said he doubted that the trial would bring closure to victims, but he described it as "a chapter in their life" they can close and no longer have to "worry about the court case, not worry about what evidence is being admitted and what evidence is not being admitted."

Walsh said measures have been taken by law enforcement at every level to make sure security is tight while at the same time making the trial accessible to the public.

He declined to comment on the trial itself except to say that he believed citizens of his city that are part of the jury pool could be fair.

Dzhokhar Tsarnaev is accused of working with his brother, Tamerlan, to set off a pair of pressure cooker bombs near the finish line of the Boston Marathon on April 15, 2013. Three people were killed, including an 8-year-old boy, and more than 260 others injured.

Three days after the bombing, Tamerlan was killed in a shootout with police and Dzhokhar was captured hours later in a dry-docked boat in nearby Watertown, Mass.

He has pleaded not guilty to more than two dozen charges related to the bombing.

On Friday, a federal judge denied defense attorneys' request for a trial delay and for a change of venue. Tsarnaev's lawyers had claimed that due to the high-profile nature of the deadly April 2013 attack "every member of the jury pool is, in effect, an actual victim of the charged offenses."