Commonwealth v. Copney, 468 Mass. 405

Defendant, a frequent overnight guest of Harvard student Brittany Smith, arranged with acquaintances to rob a marijuana seller at Kirkland House; the robbery turned into a shooting in which the victim died. Defendant fled to New York and was later arrested for first‑degree felony‑murder (predicate: attempted armed robbery) and unlawful carrying of a firearm.
After the shooting, police learned Smith’s Harvard ID had been used at locked doors around the time of the incident, Smith’s phone had recent contact with the victim, and Smith was unreachable for ~24 hours; her dorm room window was open and a light was on.
Harvard police and campus officials entered Smith’s dorm room without a warrant to check her welfare, observed a distinctive black-and-orange jacket matching witness descriptions, left, obtained a warrant, and later seized the jacket.
At trial the Commonwealth introduced limited evidence of a prior New York incident in which defendant allegedly used a similar plan (with the same accomplice) to rob a dealer at gunpoint; the judge gave multiple limiting instructions and abridged the prior-act testimony.
Defense pursued a Bowden theory (suggesting another participant was the shooter) and cross-examined investigating officers about investigative thoroughness; a prosecutor’s redirect question referencing whether an accomplice had implicated the shooter was asked, objection sustained, and the jury was instructed to disregard.

Issue	Plaintiff's Argument	Defendant's Argument	Held
Motion to suppress jacket seized after warrantless dorm entry	Warrantless entry justified by emergency aid to check on Smith’s welfare	Entry violated Fourth Amendment; defendant had reasonable expectation of privacy as long‑term guest	Entry fell within emergency‑aid exception; alternatively defendant abandoned room; suppression denied
Admission of prior bad‑act evidence (NY robbery)	Evidence relevant to modus operandi, intent, absence of mistake; probative value > prejudice	Prejudicial propensity evidence; Commonwealth must show necessity or exclude it	Prior‑act admissible for modus operandi/intent; judge properly limited scope and instructed jury; no abuse of discretion
Motion for mistrial after prosecutor’s improper redirect question (Bowden defense)	Prompt, forceful instruction to disregard cured any prejudice	Question invited impermissible inference; mistrial required	Judge did not abuse discretion in denying mistrial; jury presumed to follow instruction
Jury instruction on felony‑murder predicate	Jury convicted felony‑murder and unlawful firearm possession but acquitted armed robbery; risk verdict used firearm possession as predicate	Jury instructions limited felony‑murder to killings during (attempted) armed robbery only	Charge read as a whole limited felony‑murder to (attempted) armed robbery; no error

Minnesota v. Olson, 495 U.S. 91 (guest’s expectation of privacy in host’s home)
Commonwealth v. Entwistle, 463 Mass. 205 (emergency‑aid exception and reasonableness of welfare checks)
Commonwealth v. Peters, 453 Mass. 818 (emergency‑aid doctrine described)
Old Chief v. United States, 519 U.S. 172 (Rule 403 balancing in context of prior felony proof)
Commonwealth v. Helfant, 398 Mass. 214 (standards for admitting prior bad‑act evidence)
Commonwealth v. Bowden, 379 Mass. 472 (Bowden defense and impeachment of investigation)