A video played Friday in the Nova Scotia Supreme Court trial of Christopher Phillips shows Const. Joseph Allison and Const. Tony Blencowe questioning the accused on Jan. 21 after the accused was arrested in an Ottawa hotel.
The incident also led to the evacuation of a Halifax neighbourhood and a small rural community on the province's eastern shore after police found a large stockpile of Phillips's chemicals in two locations.
Phillips has pleaded not guilty to threatening police officers and possessing a weapon - osmium tetroxide - for a dangerous purpose.
Allison said during the video interview he wondered if an email Phillips had sent a friend about a container of osmium tetroxide was intended to be humorous.
"What was going to actually be done with them (the chemicals)?" he asked. "Were they ever going to be used to harm somebody in law enforcement or somebody you didn't like? Or was it just a tongue-in-cheek email you sent?"
The email, which has been entered as evidence, says Phillips would include instructions on how the container of osmium tetroxide is "to be used only in the event of forceful entry by the police."
It suggests poking a hole in a vial with a stick and throwing "entire box at any police officer that has decided to take up residence on your property.''
However, in the next paragraph, Phillips adds, "and I do ... stress that the box will not be designed to actually be used as a weapon.''
For almost 45 minutes of the interview with two officers, Phillips sat with his eyes closed, saying nothing as he sat listening to the detectives speak.
But then he started to open up, discussing his expertise in chemistry and assuring the RCMP officers he meant no harm.
"Even if I was being killed by a police officer, I wouldn't use it (osmium tetroxide)," said Phillips during his interview.
"I'm not that stupid. In my actual email not even I would go that far … I never once raised my hand against any authority."
He also said the chemical was a less effective weapon than a gallon of gasoline.
Phillips has said that he was using the hundreds of chemicals in his Halifax home and a cottage in Grand Desert, N.S., for experiments and for a business to extract metals from catalytic converters.
Allison said police realized it was a possibility Phillips was running a business.
Earlier in the day, an RCMP officer who was contacted by Phillips's wife, Gosia Phillips, testified he concluded comments in the email sent by the accused were a threat against police.
Const. Jonathan Fraser said Gosia Phillips approached him on Jan. 19 and asked him to dispose of dangerous chemicals that belonged to her husband.
Fraser said he initially was concerned about Christopher Phillips's mental health and was checking into whether he needed to be taken to a psychiatric hospital under provisions of the Involuntary Psychiatric Treatment Act.
However, the officer testified that after he viewed comments in an email sent by Christopher Phillips he believed the man could harm a police officer.
The trial resumes on Thursday morning.