A Suffolk County grand jury on Friday indicted four people in connection with a murder on the Southeast Expressway and another in a Dorchester house: The alleged murderer and his mother, sister and a Boston cop, who are accused of trying to help him evade capture.

Lance Holloman had already been arrested on charges he shot two motorcyclists on the Southeast Expressway on Sept. 10, one, of them, Scott Stevens, fatally, and with killing a woman in his Santuit Street home later that day. The grand jury formally indicted him for the murders and for allegedly ramming another vehicle on the Zakim Bridge before the Expressway shootings, the Suffolk County District Attorney's office reports.

Prosecutors allege that the woman he killed, Michaela Gingras, was in the rented Jeep he was driving when he rammed the other vehicle on the bridge and then shot Stevens and his father not long after on the Dorchester stretch of the Expressway.

Also indicted today: BPD Officer Monicka Stinson, 37, of Dorchester, a 10-year veteran of the force, who was charged with obstruction of justice and witness tampering. Neither police nor the Suffolk County District Attorney's office provided details of her connections to Holloman, but said she lied about being in contact with him in the hours after Stevens's murder, even though she knew he was a suspect.

In a statement, Police Commissioner William Evans said:

News of today's indictment sends a strong message that no one is above the law and that this conduct will not be tolerated. Incidents like this can erode the trust that my officers work at building each and every day in the communities we serve.

Evans said he suspended Stinson without pay on Oct. 5 as homicide and anti-corruption detectives investigated the shootings and her relation to them.

Holloman's mother, Daphne Holloman, 53, was charged with lying to investigators for allegedly telling police that she called 911 to report hearing shots in the house she shared with Holloman just ten minutes earlier when, in fact, the shots from Gingras's murder were several hours earlier. Holloman fled the scene; he was found several days later in Franklin, screaming on the side of Rte. 140.

Holloman's sister, Latoya Holloman, 36, was charged with witness intimidation for telling the person who actually rented the Jeep Holloman is charged with using to report it stolen.