Determined to not let three unsolved murder cases go cold, St. Paul police joined victims' survivors Thursday in seeking an end to the code of silence they say may be preventing assailants from being charged.

Police said the failure of witnesses and others to come forward with information has proved especially frustrating in the investigation of a triple homicide on Burgess Street in the city's North End area in 2007.

That's because two of the prime suspects in that case -- Tyvarus Lindsey and Rashad Raleigh -- already are in prison for separate murders committed elsewhere in the city.

But at a news conference drawing new attention to the unsolved crimes, police spokesman Peter Panos said it was hoped that locking up the violent offenders will give people the courage to tell police what they know about the Burgess Street case.

Investigators are also seeking information about a 2007 Frogtown homicide and a 2008 shooting death in the Dayton's Bluff neighborhood.

"Stop this code of silence," said Sharon Brown, whose son Eric Woulard, 21, was shot to death as he sat in a car in Frogtown in June 2007. "It's not helping. It's killing us."

A look at the cases:

North End

On March 23, 2007, intruders broke into a home in the 200 block of Burgess Street and shot and killed Maria McLay, 32, her boyfriend Otahl Saunders, 31, and her daughter Brittany Kekedakis, 15. Two younger children escaped.

Raleigh, charged in the beating death of basketball star-turned-probation officer Howard Porter, pleaded guilty to first-degree murder in that case in return for a deal with prosecutors that he would not be charged by Ramsey County for the triple murder.

News that he may have been involved in the North End case surprised observers. But such was the viciousness of the homicides that several Burgess Street residents declined -- out of fear -- to comment about the development last August.

Lynnette Hartling, McLay's mother and Kekedakis' grandmother, said Thursday: "I know someone out there does know something. ... Be brave and come forward."

Frogtown

On June 16, 2007, Woulard was found fatally shot in a vehicle when police reported to a call of shots fired in the 600 block of Van Buren Avenue.

A few days later, police arrested a 24-year-old suspect, but he was not charged.

Dayton's Bluff

On Oct. 25, 2008, Jaques Dortch, 18, was sitting in a parked car with friends near her home at 6th and Forest Streets when a lone gunman approached and fired shots into the car, killing her instantly.

People with information about the murders are asked to call police at 651-266-5650 or Crime Stoppers at 1-800-222-TIPS. Crime Stoppers is offering rewards of up to $1,000 in each of the three cases.

An additional amount up to $15,000 also is available in the Burgess Street case.

Anthony Lonetree • 612-673-4109