Defence lawyers are set to launch their case at the Robert William Pickton murder trial on Tuesday, after a weeklong delay.

The defence had been prepared to begin its argument in the B.C. Supreme Court in New Westminster on Aug. 27, but Judge James Williams ruled another week was needed to give lawyers on both sides time to prepare.

The delay was one of many since the highly publicized trial began Jan. 22.

Pickton, a pig farmer from Port Coquitlam, B.C., is on trial for the deaths of six of the women who went missing between 1997 and 2001 — Sereena Abotsway, Mona Wilson, Andrea Joesbury, Brenda Wolfe, Marnie Frey and Georgina Papin.

He faces a total of 26 first-degree murder charges in connection with the deaths of women who went missing from Vancouver's Downtown Eastside.

Pickton, who has pleaded not guilty, will be tried on the remaining 20 counts at a later date.

The prosecution wrapped up its case Aug. 13, after calling 98 witnesses.

The CBC's Susana da Silva, who has been following the trial, said defence lawyers have not disclosed any details about the argument they will be presenting.

"They've been very tight-lipped about what they plan on doing," she said Tuesday before proceedings got underway in the courtroom.

She said that during cross-examination of Crown witnesses, the defence focused on several key points, including Pickton's possible mental slowness, the potential lack of credibility of key witnesses, and the possibility that others may been involved in or carried out the killings.

Da Silva said it is possible the defence will round out these points as it presents its case.

It remains uncertain if defence lawyers will call Pickton to the stand.

Crown lawyers are required by law to tell the defence team about their witnesses, but defence lawyers are obligated only to inform the other side of experts they plan to call, not witnesses.

The defence team has said it expects its argument to take three weeks to complete, much less time than the Crown's argument, which took seven months.