The weapons-related trial for a Calgary gangster who is also accused of murder has been delayed because the Calgary Police Association's president is charged with perjury.

Sgt. Les Kaminski was the Crown's key witness at Nick Chan's trial. Kaminski was charged last month with perjury and assault with a weapon stemming from his testimony at a 2011 trial.

Once it was learned Kaminski was accused of lying under oath, Chan's lawyer requested documents from the Alberta Serious Incident Response Team (ASIRT) investigation so that he can properly cross-examine the Calgary officer.

"Any time you find out that a witness in your trial was charged with perjury in a previous trial, you have no choice but to get to the bottom of it," Bates said.

A decision on whether or not Kaminski's search would be deemed legal this time around was supposed to be delivered Thursday but was delayed because of his charges.

Kaminski was elected as the new president of the police union in November.

Chan was pulled over by Kaminski and his partner in a traffic stop in 2010 but after a search of his vehicle, a .32-calibre and semi-automatic handgun were found under the driver's seat.

Chan was originally acquitted in 2011 after a judge ruled Kaminski's search was illegal. But the Alberta Court of Appeal overturned that decision and ordered a new trial.

Not a 'reliable witness," found judge in different trial

Kaminski's charges relate to a 2008 arrest. The man was later acquitted of uttering threats to a police officer because Provincial Court Judge Terry Semenuk found Kaminski "was not a credible or reliable witness."

Nick Chan, suspected of leading his group — the FOBs — through the most violent gang war ever to take place on Calgary streets, is also charged with first-degree murder.

He's accused of ordering a hit on rival gangster, Kevin Bontogon, that instead ended with the death of Kevin Anaya in 2008. Chan also faces a charge of conspiracy to commit murder for the alleged plot on Bontogon's life.

That trial is set to take place on Oct. 2.

Bates is expected to receive disclosure by March 1. Chan will be back in court March 20.