LOWELL — Prosecutors dropped all charges faced by a 30-year-old Lowell man who was accused of firing two gunshots at a man in a car near Merrimack and Cabot streets last year because a key witness in the case refused to testify, according to court records.

David Cifredo was arrested in July of last year and accused of firing two gunshots at a vehicle near the intersection, with one of the bullets striking the alleged victim’s car, according to police. There were no reported injuries.

Cifredo was indicted on charges of attempted assault and battery with a firearm, assault with a dangerous weapon, carrying a firearm without a license (subsequent offense) and carrying a loaded firearm without a license, according to court records.

Cifredo was scheduled to face on trial on those charges starting Monday, but prosecutors instead dropped the case as they said in a court filing that “given the current state of the evidence the commonwealth cannot sustain its burden at trial.”

Motions filed in the case say the alleged victim was the only eyewitness to the incident, and that he invoked his 5th amendment rights and refused to testify at trial even though he previously testified at a dangerousness hearing for Cifredo in Lowell District Court.

Prosecutors sought to show a jury transcripts of that man’s earlier testimony, but motions filed in the case say the alleged victim lied during his testimony in Lowell District Court.

Defense attorney Jamal Aruri, of Lowell, argued that the past testimony amounted to “unreliable hearsay” since the alleged victim admitted he lied in that testimony.

Superior Court Judge Robert Ullmann allowed Aruri’s motion to exclude the alleged victim’s prior testimony from trial, writing that “based on the witness’s admission that he lied during the (dangerousness hearing), allowing the commonwealth to use that testimony at trial without an opportunity for the defense to cross-examine the witness would violate the confrontation clause of the U.S. Constitution.”

Shortly after Ullmann made that ruling, prosecutors dropped all charges against Cifredo.

Court records indicate the alleged victim is currently serving a sentence in state prison.

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