RIVERHEAD - A grand jury was shown evidence behind closed doors today that could lead them to upgrade charges against the wife of the man accused of killing four people at a Medford drug store.

According to court documents, Melinda Brady has admitted to driving the getaway car and plotting with her husband, David Laffer, to rob Haven Drug store on Father's Day.

Brady has been charged with robbery and obstruction of governmental administration, but trial lawyer Bruce Barket says he believes she will most likely face a felony murder charge.

Officials say Brady also admitted to using pain killers after an oral surgery and told police that Laffer used her prescription to steal drugs from the store on the day of the shootings.

Barket says he doesn't expect the grand jury to make a final decision on the charges for about four days.

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