Investigators determined 652 women and girls were captured in photos and videos by Yin Yeung Derek Chan, who had been posting the imagery online.
A 39-year-old Saanich man has been sentenced to 4½ years in prison in what Saanich police are calling the most prolific case of voyeurism ever prosecuted in Canada, involving more than 650 women and girls.
Yin Yeung Derek Chan was sentenced in Victoria provincial court on Thursday.
He pleaded guilty on Oct. 1, 2025, to four counts related to voyeurism, including surreptitiously recording people in a place where they could reasonably expect privacy, observing and recording for a sexual purpose, making child pornography and publishing a recording that was obtained in the commission of a crime.
He also pleaded guilty to breaching three separate conditions, two of which related to a previous conviction.
Chan was previously convicted of voyeurism after being caught filming a woman in a mall change room in the capital region.
Saanich police began investigating in January 2024 after a Saanich detective was made aware that voyeuristic photos and videos were being uploaded to a popular image-based social-media site from somewhere in Saanich.
The investigation, which also involved the B.C. Integrated Child Exploitation Unit, led detectives to Chan, who was arrested April 11, 2024, in his Saanich home. Detectives seized devices from the home with thousands of images and more than 28 hours of video recorded between April 1, 2017, and Nov. 30, 2023, without the knowledge of the women and girls involved.
The images and videos were taken inside businesses, at beaches and, in some instances, through the windows of private residences across the region.
Investigators determined that 652 women and girls were captured in the photos and videos. Police said many of the images were posted to websites around the world, and formal requests were made to have them removed.
Detectives were able to identify and contact 40 victims, 16 of whom submitted victim impact statements for sentencing. About 90 per cent of the women and girls were photographed or recorded up their skirts — known as upskirting — while 12 to 15 victims were recorded in change rooms and five were recorded through windows.
The rest were victimized on beaches.
Sixty-four victims were determined to be underage, five of whom were identified by police.
Many victims said they had changed their clothing choices after learning they had been photographed, opting for modest, oversized or androgynous clothing, said Judge Lisa Mrozinski.
One young victim said in her statement she was devastated and felt highly exposed and powerless when she learned from police that she was one of Chan’s victims, Mrozinski said during the sentencing hearing.
“You treated her body as something you were entitled to,” the judge said.
Another victim called Chan’s behaviour “deliberate, predatory and deeply disrespectful.”
“You, a stranger to her, made a conscious decision to violate her body, her privacy and her dignity for your own gratification,” Mrozinski said.
The victim no longer feels safe in public places and looks for cameras when she is out. She is wary of other people near her in public and is constantly aware of how she stands, keeping her legs together. She thinks about how she moves and how she dresses, Mrozinski said.
“An act as basic as walking outside of the home has been permanently altered by your conduct,” the judge said.
Another victim said she is distressed by the possibility that her image remains on the internet and could be seen by friends or colleagues.
That fear creates a “persistent sense of vulnerability,” the woman said.
All of the victims’ identities are protected by a publication ban.
Mrozinski called Chan’s impact on the women and girls “frankly incalculable,” and said he has shown a lack of insight into his offending.
She said it is “concerning” that Chan considers himself rehabilitated after spending more than a year in custody and taking some courses, none of which came close to addressing his offending behaviour. She said he has proven himself resistant to treatment, but without it, he represents a “considerable danger” to the community.
In a statement, Chan expressed remorse for his behaviour and sought forgiveness.
“You write that violating others is ‘just not worth throwing away my life,’ and that you’ve decided to quit your pornography addiction and explore new hobbies, one of which is astronomy, where you intend to spend time stargazing,” Mrozinski said.
Mrozinski questioned Chan’s claim, saying it’s not believable that during his time on remand, Chan has learned how to control whatever impulses led to his offending over the course of six years.
The evidence indicates there is a “large, enthusiastic” audience of voyeurs consuming the materials Chan produced of women and young girls “stripped of their dignity and reduced in their essence to a body part,” Mrozinski said. Chan’s decision to upload photos and videos fuelled that demand, she said.
His sentence must send “an unequivocal message” to Chan and others that surreptitiously recording women and children and uploading the images and videos to the internet is “intolerable in civil society,” Mrozinski said.
“The sentence must serve to discourage you personally [in a] way that your previous sentence did not,” she said.
Chan was released with conditions following his initial arrest in April 2024 and arrested again on Jan. 30, 2025. He was detained and has remained in custody since then.
With credit for time served in pre-trial custody, he has a little more than two and a half years remaining in his sentence.
Saanich police said detectives continue to work to identify all the women and girls in the case.
Anyone who believes they may be one of the hundreds of unidentified victims is asked to email: [email protected]
Greater Victoria Victim Services has been assisting many of the identified victims and is offering support to anyone who comes forward.