Dangerous sex offender to serve indeterminate sentence, Vancouver police say

John Ambrose Seward was declared a dangerous offender on April 30, 2026. (Handout)

A British Columbia judge has sentenced a high-risk sex offender to an indeterminate prison term after declaring him a dangerous offender.

John Ambrose Seward was charged with assaulting a woman in East Vancouver in October 2022. At the time of the attack, Seward had been serving a 10-year supervision order in the community following prior convictions for sexual assault, aggravated assault and sexual assault with a weapon.

Seward was convicted of the 2022 attack in 2024, prompting the B.C. Prosecution Service to pursue a dangerous offender designation.

In a news release Thursday, the Vancouver Police Department said prosecutors spent about 18 months presenting evidence in support of the designation, “which can only be imposed when there is no reasonable expectation that the offender’s risk will be manageable in the community.”

The dangerous offender designation and indeterminate sentence were delivered by a provincial court judge on April 30, according to police.

“Protecting communities from high-risk sexual and violent offenders is a priority for the Vancouver Police Department and the B.C. Prosecution Service,” said Vancouver police Const. Megan Lui in a statement.

“One way to do this is by making dangerous offender applications in appropriate cases, and the investigation and prosecution of Seward was one of those cases.”

Vancouver police issued a public warning in 2021 when Seward moved into a halfway house in the city.

The then-33-year-old posed significant risk to women and was prohibited from visiting any parks or travelling to central Vancouver Island, the warning said.

Prior to the public alert, Seward had served five and a half years in prison for a string of assaults in the Port Alberni area. One of those incidents involved Seward sexually assaulting a woman at knifepoint.

With files from CTV News Vancouver’s Meagan Gill Erickson