The jury in the Robert William Pickton murder trial has heard a jubilant Pickton tell an undercover police officer that he wanted to "make it an even 50" before going on to "do another 25 new ones."

The jury in B.C. Supreme Court in New Westminster on Tuesday watched a videotaped jail cell conversation between the officer and Pickton. The exchange was filmed immediately after the Port Coquitlam pig farmer was returned to his cell following his interrogation in February 2002.

During the video, a guard brings him dinner and Pickton is unfailingly polite, thanking the guard and delivering coffee to his cellmate.

Pickton perks up as the RCMP officer begins to talk about his own charges for attempted murder — a story concocted as part of his role as a cell plant.

"But you're nothing like mine," says Pickton.

As he spoons up his dinner, Pickton gestures with one hand to five fingers, and then zero.

"Five-zero. Fifty?" the undercover officer says in disbelief, and asks what proof police have.

"Old carcasses," Pickton says, although police had not mentioned that during the interrogation. In fact, at this point in the search, no human remains had been found.

Calls himself 'Mr. Sloppy'

The undercover officer then gives his own hints, saying he uses the ocean to dispose of things.

Pickton takes his plate, and goes to sit beside the officer. He lowers his voice, and as he continues to eat, Pickton says, "Did better than that — a rendering plant."

(Rendering plants take excess animal tissue from slaughterhouses and farms to extract usable material. There is one in Vancouver's Downtown Eastside.)

Then Pickton says: "I was gonna do one more, make it an even 50 … make the big Five-0."

'…it's amazing how many people feel they have to unload.'—Defence lawyer Donna Turko

With little prodding, he continues, calling himself "Mr. Sloppy."

He raises four fingers: "Four I was sloppy with," he says. 

Pickton then says, "So, let everything die for a while," and then, laughing, adds, "do another 25 new ones."

Seconds later, he looks straight at the camera in the cell, says "Hello" and waves at it.

Pickton is being tried on six of the 26 charges of first-degree murder in the deaths of missing women from Vancouver's Downtown Eastside, with a second trial to be held later. He has pleaded not guilty to all charges.

The jury also saw Pickton saying he would be "bigger" than the Green River killer, who confessed to killing 48 women in Washington state.

Undercover plants common, says lawyer

Donna Turko, a criminal defence lawyer who's observing the trial for CBC News, said it's common for police to plant undercover officers in cells with suspects to glean information from them.

"Defence counsel tell their clients, 'Don't speak to anybody,'" she told CBC News on Tuesday.

She said lawyers often advise their clients to stay clear of those who appear to be friendly or sympathetic in jail for fear that their words could be used against them later in court.

"But it's amazing how many people feel they have to unload," she said.

On Monday, the jury heard part of the lengthy videotaped conversation between Pickton and the officer, in which Pickton recalled childhood memories and said he wanted to leave the pig-farming business when he was 40.