From a reporter covering the proceeding live: The Judge said there was no legal obligation to call the police and report Dzhokhar, but there was a moral obligation. He said "It goes to his character and the background of the offense" that when the FBI asked for help, he removed evidence.

The judge did not believe the taking of the items was solely to protect Dzhokhar, as he did not take the iconic white cap. He said the motive was mixed: "conceal, cover up, transport evidence, but also to take valuable pieces of property"

The relatives of slain police officer Sean Collier, did not testify.

Dias pleaded guilty to two obstruction counts. Count One charged him with conspiring with Azamat Tazhayakov to violate 18 U.S.C. § 1519 by agreeing to alter, destroy, conceal, and cover up Tsarnaev's laptop and his backpack containing fireworks, with the intent to impede, obstruct, and influence the FBI’s investigation into the Boston Marathon bombings. Count Two charged him with obstruction of justice based on the alteration, destruction, concealment, and covering up of the same objects. From the Government's sentencing memorandum:

There is no evidence that Kadyrbayev was aware of Tsarnaev’s plan to bomb the Boston
Marathon or played any role in that terrorist attack. Nevertheless, Kadyrbayev conspired with
Tazhayakov to obstruct a terrorism investigation and affirmatively acted to impede the bombing
investigation at the critical moment when the investigation was intensely focused on locating the Tsarnaev brothers and thwarting further acts of violence.

...Rather than heeding the FBI’s plea for help from the public, the defendant and
Tazhayakov interfered with the administration of justice and impeded the investigation by
causing the unnecessary expenditure of substantial government resources and inhibiting the investigative efforts of federal law enforcement officers.

The Government did not claim Dias would have prevented Collier's murder had he called the police when he learned Dzhokhar was involved in the bombing:

The government does not ask the Court to find that a call by Kadyrbayev to the police
would have resulted in earlier apprehension of Tsarnaev. The moral obligation at issue is rooted
in the possibility that calling the police could have made a difference, regardless of how one
assesses the likelihood that it would in fact have made a difference

As to the application of the terrorism enhancement, which bumped Dias' guidelines up to 360 months to life, the Government wrote:

Because Kadyrbayev’s crimes, while serious,
are unlikely to be repeated and did not include any crimes of violence, the Government believes
that a consideration of the factors specified at 18 U.S.C. §3553(a) demonstrate that a sentence of
7 years is reasonable.

The statutory maximum was 25 years (less than the guidelines.) Dias has already served 2 years in pretrial confinement. He has been in 23 hour a day segregation. He will be deported at the end of his sentence.

Azamat Tazhayakov and Robel Phillipos will be sentenced later this week. Both went to trial and lost. Azamat was found guilty of obstructing justice with respect to Tsarnaev's backpack (but not the laptop.) Azamat, who went to trial first, later agreed to testify against Robel, Dias and Tsarnaev. (He testified for the Government at Robel's trial.) The Government is asking that Azamat be sentenced to 48 months. (Court Document 594). His guidelines, like Dias', are 360 to life due to the terrorism enhancement, but the maximum he can get by statute is 25 years.

Robel was convicted of making false statements in a terrorism investigation. The maximum sentence is 8 years per count.