Edward Downey will go to trial on two counts of first-degree murder for the deaths of a Calgary mother and her five-year-old daughter, after his application to sever the charges was denied by a judge.

Sara Baillie, 34, and Taliyah Marsman, 5, were killed in July 2016.

Justice Beth Hughes delivered her decision Tuesday after lawyers for both sides made arguments last month.

Downey's defence team of Gavin Wolch and Meryl Friedland had asked the judge to allow his two counts of first-degree murder to be severed, which would mean he'd be tried twice.

The details discussed during the hearing — which include the reasons argued by the defence lawyers and Crown prosecutors Carla McPhail and Ryan Jenkins — are protected by a publication ban.

Trial to begin November

In July 2016, police were called to Baillie's home after she failed to show up for work. Officers discovered the mother's body in her basement apartment in the northwest community of Panorama Hills.

An Amber Alert was activated for the child when investigators realized she was missing. About a week later, Marsman's body was discovered about eight kilometres east of Calgary near a rural road close to Chestermere.

Downey was known to both victims, according to police.

His criminal history involves convictions for pimping, drug trafficking and weapons offences dating back more than two decades.

Following a preliminary inquiry last year, Downey was committed to stand trial on two counts of first-degree murder.

The three-week trial begins in November.