THE CANADIAN PRESS -- VANCOUVER - Four Mounties tasked with investigating one of British Columbia's bloodiest gang shootings are now facing criminal charges, and the mother of an innocent bystander worries the trials against those accused of killing her son will now become even more complicated.

The charges against the officers relate to allegations that one had an inappropriate relationship with a witness while police were investigating the deaths of the six people gunned down in a highrise apartment building in Surrey in October 2007.

The RCMP insisted Thursday that the charges against the officers won't affect the criminal case against the accused killers.

But Eileen Mohan, whose 22-year-old son Chris was among two people simply in the wrong place at the wrong time, worries the scandal may give defence lawyers "ammunition" in court.

"Obviously, it will raise serious questions about witness tampering, overtime being charged when it shouldn't have been. The defence lawyers... will try to make this case even more complicated," Mohan said in an interview.

"They (the accused) cannot be let go just on a technical ground."

Still, Mohan praised the work of the other RCMP officers working on the case.

"I am very disappointed about the behaviours of a handful of RCMP officers who make the other officers who work very diligently, very hard look bad."

Special prosecutor Christopher Considine approved a total of 20 charges against officers Sgt. Derek Brassington, Staff Sgt. David Attew, Cpl. Paul Johnston and Cpl. Danny Michaud. The recommendation followed an outside investigation by the Ontario Provincial Police.

The officers were all involved in probing the deaths, discovered after neighbours complained of a foul odour coming from a condo unit.

Police quickly concluded Mohan and 55-year-old Ed Schellenberg weren't connected with the gang war believed to have sparked the slaughter.

Earlier this year, the province's Criminal Justice Branch announced Considine was looking into allegations of an inappropriate relationship between an officer involved in the investigation and a witness.

Chief Supt. Janice Armstrong of the RCMP acknowledged Thursday the charges against the officer could further erode the public's confidence in the force, but she insisted the criminal case related to the killings themselves won't be affected.

"I don't think this helps the public confidence, but I think what we've demonstrated through this process is that we're determined to hold members accountable if there are any wrongdoings, if there is any criminal behaviour," Armstrong told reporters at the RCMP's headquarters in Vancouver.

"The Crown counsel team working on the prosecution of the individuals charged with the homicides has reviewed the case in light of the OPP investigation. Crown counsel has informed us that there has been no change to the decision to prosecute those charged."

An indictment filed with the court this week indicates Brassington faces seven counts, including breach of trust, in his management of a witness, identified only as Jane Doe.

He is also accused of attempting to obstruct justice by compromising the integrity of witnesses, and of trying to obstruct justice in relation to the investigation of police misconduct.

The indictment also alleges Brassington defrauded the RCMP in the form of wages or overtime pay he was not entitled to, as well as claiming for expenses to which he was not entitled.

Attew faces six counts, including breach of trust related to witness Jane Doe, fraud and obstruction of justice.
Johnston faces four counts and Michaud, three, of breach of trust and obstruction of justice.

A fifth officer involved in the case was under investigation for unrelated charges of fraud and attempted fraud in connection with overtime claims. That investigation was not part of the special prosecutor's assignment.

Six people have been charged in the gang slayings, which were among the first volleys in a gang war that would play out on the streets of Vancouver in the following years.

One of them, Dennis Karbovanec, pleaded guilty in April 2009 to three counts of second-degree murder and conspiracy to commit first-degree murder in the slayings. James Kyle Bacon, Quang Vinh Thang Le, Matthew James Johnston, Cody Rae Haevischer, and Sophon Sek still face trial.

The four officers involved in the investigation had been suspended with pay but Armstrong said the force has moved to suspend them without pay, pending internal code-of-conduct investigations.

Armstrong said all victims' families were informed by the force of the latest development.

"There’s no question this is the last thing these families should have had to deal with in the context of the murder of their loved ones," said Armstrong.

The accused officers are scheduled to make their first appearance in court on July 11.