TORONTO (AP) _ The defense lawyer in a sex-murder trial riveting Canada hinted for the first time Thursday that Paul Bernardo _ accused of abducting, raping and killing two schoolgirls _ may take the stand to testify.

``We'll hear from him ... at the appropriate time,'' said lawyer John Rosen during a third day of tough cross-examination of Bernardo's ex-wife, Karla Homolka.

Much of Thursday's questioning concerned Homolka's younger sister, Tammy, who choked to death on her own vomit in December 1990 after Bernardo and Homolka sexually assaulted her. They had given the 15-year-old girl alcohol, sleeping pills and an anesthetic.

Homolka has said she took part in the assault because Bernardo wore her down with threats and beatings. She claims he later used the incident to blackmail her into helping him in the sex slayings of the two schoolgirls, Leslie Mahaffy, 14, and Kristen French, 15.

Homolka told the court Thursday she was afraid Bernardo would grab Tammy ``on the street'' and rape her if she didn't help him drug and sexually assault the girl.

But Homolka conceded she never warned Tammy to stay away from him.

Rosen suggested Homolka willingly took part in the assault and cared more about saving her own skin than keeping Tammy alive.

Homolka, 25, said she never thought her sister would be physically hurt by Bernardo's plan to drug and rape her and she felt it was better than another option.

``I was afraid that Paul would do this regardless,'' she told the jury in a shaky voice as her mother, Dorothy, and surviving sister, Lori, watched from the second row of the courtroom.

``I was afraid he would grab her on the street and rape her and I didn't want her to go through that.''

Bernardo, 30, isn't on trial in Tammy's death, but Judge Patrick LeSage told jurors evidence about the assault could be used to shed light on the couple's relationship.

Bernardo has pleaded innocent to two counts of first-degree murder and seven other charges relating to the kidnapping, rape and killing of Mahaffy and French.

Homolka, a former veterinary assistant, is serving a 12-year sentence for manslaughter in the two deaths _ a sentence that also took into account her involvement in Tammy's death.