Daniel Silva, 21, of Cambridge is charged with drug crimes and possession of a Ruger handgun Tsarnaev and his brother, Tamerlan, allegedly used to shoot a Massachusetts Institute of Technology police officer. Silva appeared at a hearing in federal court wearing a tan jail uniform and chained at wrist and ankle.
Tsarnaev could face the death penalty if he is convicted of setting off the bombs that killed three people and injured more than 260 at the marathon finish line on April 15, 2013. A college friend was recently convicted of removing items from Tsarnaev's dorm room at the University of Massachusetts Dartmouth after the bombing and others face similar charges.
Silva, who allegedly once told a police officer he was Tsarnaev's "best friend," is not charged with involvement in the bombing or with trying to help Tsarnaev after the fact. The indictment charges him with possession of heroin with intent to distribute and possession of a gun with the serial number removed.
The brothers allegedly killed MIT Officer Kenneth Collier a few days after the bombing. Tamerlan was killed in a confrontation with police hours later.
"I've read what's in the papers. The papers are saying that law enforcement officials are saying the gun was the gun that was used, but again, that's not been charged," Silva's lawyer, Jonathan Shapiro, told reporters after the hearing.
Prosecutors said Silva faces up to 20 years in prison. Shapiro did not request bail but said he might ask for it later.
Some of Silva's friends cried during the hearing when they saw him in shackles and later shouted obscenities at reporters and camera crews leaving the courthouse.
During an arrest in November at a Boston subway station, Silva allegedly spoke of his friendship with Tsarnaev: "I smoke a lot of weed every day because my best friend was the bomber. "