Julie Crocker, 33, was an account manager at a Toronto radio station. (Canadian Press)

The Toronto-area man accused of killing his wife and another woman more than two years ago testified on Wednesday that he had nothing to do with their deaths.

Christopher Little, from Markham, Ont., spoke for the first time at his trial in Ontario Superior Court. He has pleaded not guilty to two counts of first-degree murder in the deaths of his wife Julie Crocker, 33, and Paula Menendez, 34.

Both were found dead in Crocker and Little's Markham home on Feb. 17, 2007. Crocker's body was found in the master bedroom with her throat slit. Menendez's body was found with yellow rope tied around her neck.

Little, 37, and Crocker had been married for 10 years and had two young daughters.

Crocker had been having an affair with Toronto sportscaster Rick Ralph for several months before her death. Menendez was Ralph's estranged wife.

For the last six weeks the Crown built a case depicting Little as an obsessive husband who killed his wife and Menendez in a jealous rage.

Little tried to prove infidelity

It was the defence's turn on Wednesday. Little's lawyer John Rosen asked him whether he killed his wife, whether he kidnapped and killed Menendez ,and whether he was involved in their deaths in any way. Little replied "no" to all three questions.

Paula Menendez, 34, was a physiotherapist in Toronto. (CBC)

Little told a Newmarket courtroom packed with loved ones of the two victims that he wanted to work things out with his wife despite what he believed were her numerous acts of infidelity.

He calmly admitted to buying a kit to test for traces of semen on Crocker's clothes. He also admitted to installing a GPS device in Crocker's car.

Little said he was looking for proof of her affair with Ralph, which she had previously denied having.

"I didn't want a relationship with Julie having another relationship on the side. I wanted an exclusive relationship with my wife," Little said.

He recounted finally catching Crocker and Ralph in the family home together shortly after their separation in the summer of 2006.

"After finding Julie and Rick together in the house, everything was out in the open. All the truth came out — it was basically Julie making a conscious decision of Rick versus me."

Little only appeared to show emotion when speaking about how hard his separation with his wife was on one of his daughters. Little broke down at that point and had to take a couple minutes to recompose himself.