Commonwealth v. O'Neil

Massachusetts Appeals Court · 2001 · Evidence

51 Mass. App. Ct. 170 (2001)

Updated August 22, 2026

Evidencebias impeachmentmotive to liepromises rewards inducementsineffective assistance of counseljoint venturegrand jury probable causeextrinsic evidence

Facts

Deborah O'Neil and her son Steven were convicted as joint venturers in an arson actually carried out by Michael O'Neil and Charles Rosinski. At trial, Rosinski was the sole witness placing Deborah at the scene and implicating her as an instigator and facilitator of the crime. Before trial, the Commonwealth disclosed a notice stating that Rosinski was expected to testify against Deborah and Steven and that he anticipated pleading and receiving probation. Deborah's counsel mentioned an expected deal in opening but failed to bring the notice effectively before the jury or use it to expose Rosinski's possible bias.

Issue

As to Steven, whether the grand jury heard sufficient evidence to establish probable cause that he knowingly and intentionally participated in the arson as a joint venturer. As to Deborah, whether trial counsel's failure to use the Commonwealth's notice of expected leniency to impeach Rosinski's credibility deprived her of effective assistance of counsel.

Rule

To establish probable cause for joint venture liability, the Commonwealth must present evidence that the defendant was present at the scene, intended to commit the crime or knew another intended to commit it, and by express or implicit agreement was willing and available to assist; intent may be inferred from the circumstances. A criminal defendant has the right to expose any circumstance that may materially affect an adverse witness's testimony by showing bias, prejudice, or motive to lie, including any statement or communication that reasonably implies the government may confer or withhold future advantages depending on the witness's cooperation, and such evidence may be proved extrinsically as well as through cross-examination.

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One of 10 multiple-choice questions for this case. Pick an answer to see why.

In a burglary trial in Worcester, the prosecution's key witness, Tyler Boone, has his own related charges pending. Before trial, the prosecutor sent defense counsel a letter stating that Boone is expected to testify against Nina Patel and that Boone is anticipated to plead later and receive probation.

At trial, Boone denies that anyone promised him anything. Nina seeks to introduce the letter to show Boone's bias and motive to curry favor with the prosecution. How should the court rule?

Explanation. The governing rule is that a defendant may expose any circumstance that may materially affect an adverse witness's testimony by showing bias, prejudice, or motive to lie. That includes statements or communications reasonably implying that the government may confer future benefits depending on the witness's cooperation. The majority also states that such bias evidence is not merely collateral and may be proved by extrinsic evidence as well as through cross-examination.