Two former classmates of Boston Marathon bombing suspect Dzhokhar Tsarnaev are due to appear in Federal court Tuesday in relation to charges that they sought to conceal evidence from the Federal Bureau of Investigation (FBI) of the younger Tsarnaev brother’s involvement in the April 15 bombings, which killed 3 people and wounded more than 260 others.

Dzhokhar Tsarnaev, 20, has been charged with capital crimes in relation to the bombings and remains incarcerated. His older brother Tamerlan Tsarnaev, 26, was killed in a shootout with police four days after the bombings.

According to a court affidavit filed last week, Dias Kadyrbayev (19) and Azamat Tazhayakov (19), former students at the University of Massachusetts-Dartmouth, did “knowingly alter, destroy, conceal, and cover up tangible objects with the intent to impede, obstruct, and influence an investigation…within the jurisdiction of the Federal Bureau of Investigation.” If found guilty, the two defendants, both Kazakh nationals, could face deportation or more than 20 years in prison and over $250,000 in fines.

The defendants were originally detained April 20 on immigration violations and were later charged with intent to obstruct the investigation into the bombings. It is alleged that days after the bombing and upon receiving cell phone texts from the suspect instructing them to “go to [Tsarnaev’s dormitory] room and take what’s there,” Kayrbayev and Tazhayakov proceeded to remove items that might incriminate the younger suspect.

Among the items taken were several fireworks casings, from which the explosive powder had been removed, a laptop, a backpack and a jar of Vaseline. The materials were placed in a garbage bag and put into a dumpster behind the dorm where Kadyrbayev and Tazhayakov resided.

The affidavit also mentions a third acquaintance, American Robel Phillipos, who is not being tried alongside the others but allegedly assisted them in falsifying their alibis.

Robert Stahl, Kadyrbayev’s attorney, released a statement last week saying the indictment, though “not unexpected,” was “certainly disappointing.” He insisted that the suspects had cooperated with federal investigators and had assisted them in obtaining evidence crucial to the case, including the items removed from Tsarnaev’s dormitory.

Arkady Bukh, Tazhayakov’s attorney, has declared the case against his client to be “a witch-hunt,” stating in an interview with Voice of Russia that “[t]here was no motive and no order from Tsarnaev to destroy evidence…. Unfortunately, we couldn’t convince them. At this time there is little left but to go to trial.”

Whatever the actions and motives of Kadyrbayev and Tazhayakov, a far bigger question pertaining to “obstruction” in relation to the April 15 events has to do with the actions of the US government itself.

On May 22, in what amounted to the extra-judicial execution of an unarmed witness with close ties to Tamerlan Tsarnaev, the FBI shot and killed 27-year-old Ibragim Todashev in his Florida home. Todashev had been a friend of the older Tsarnaev brother when he was living in Massachusetts. The circumstances surrounding his killing, after hours of FBI interrogation, have never been explained. The agent responsible for Todashev’s death has not only not been prosecuted, his name has been withheld from the public.

Todashev, like the Tsarnaevs of Chechen birth, may have had information concerning Tamerlan Tsarnaev’s links to Islamist terrorist groups in Russia’s North Caucasus region as well as the older Tsarnaev brother’s ties to the FBI and other US intelligence and police agencies. The FBI had investigated Tamerlan Tsarnaev after receiving warnings of his terrorist sympathies and connections from Russian security officials, but, according to FBI officials, concluded that there was nothing suspicious about him.

US officials allowed Tamerlan Tsarnaev to travel unimpeded to Dagestan in 2012 and remain there for six months, during which time he reportedly made contact with various Islamist separatist and insurgent groups.

Last month, federal officials refused to release the autopsy findings regarding Todashev’s death. Shortly afterward, Florida officials refused to conduct a separate state investigation into Todashev’s killing on the grounds that to do so would be “inappropriate.”

The American media has remained virtually silent on the state execution of a potentially key witness in the Boston bombings case and made no attempt to investigate the circumstances of his death.