In 1869, Parliament enacted a criminal law prohibiting abortion, which remained virtually unchanged until 1969.

In the 1960's, a push to legalise abortion came from the Canadian Medical Association, the Canadian Bar Association, women's groups, some liberal churches, social welfare agencies, the Canadian Labour Congress and the Humanist Fellowship of Montreal (whose president was Dr Henry Morgentaler).

In 1969, the criminal law was amended to legalise certain abortions performed by a qualified doctor in an approved hospital. Under section 251 of the Criminal Code, a therapeutic abortion committee of at least three doctors was required to decide whether the continuation of the pregnancy would endanger the woman's life or health.

In the 1970's, Dr Henry Morgentaler challenged the authorities by performing illegal abortions and opening private clinics. In 1975, he was sentenced to 18-months imprisonment, but released after ten months following a heart attack. He was aquitted three times by juries and in 1976, the Quebec government dropped all charges.

In May 1983, Dr Morgentaler opened a clinic in Winnipeg and Toronto, both of which was raided by the police. A jury acquitted all three doctors in November 1984. The Ontario Attorney General announced he would appeal the jury acquittal. In October 1985, the Ontario Court of Appeal set aside the jury acquittal and ordered a new trial.

Dr Morgentaler appealed, then on January 28 1988, the Supreme Court of Canada struck down the abortion law as contrary to section 7 of the Charter of Rights and Freedoms. Chief Justice Dickson stated that:

'Section 251 clearly interferes with a woman's physical and bodily integrity. Forcing a woman by threat of criminal sanction, to carry a foetus to term unless she meets certain criteria unrelated to her own priorities and aspirations, is a profound interference with a woman's body and thus an infringement of security of the person.'

Anti-abortion activist Joseph Borowski appeared before the Supreme Court in October 1988, presenting a case for unborn children being protected as persons under the Charter of Rights and Freedoms. In March 1989, the Court ruled unanimously that since section 251 had been struck down by the Morgentaler decision, Borowski's challenge to it was moot.

In 1989, a celebrated case saw two former boyfriends attempting to prevent their babies being aborted. The Supreme Court rejected the argument that a prospective father had an interest in a baby allowing him to prevent an abortion.

The federal government attempted to introduce legislation to return abortion to the Criminal Code. Bill C-43 would permit abortion if the pregnancy threatened the woman's physical or mental health. The Bill was defeated in the Senate on January 31, 1991 in a dramatic tie vote.

Through the 1990's, Dr Morgentaler continued to open abortion clinics around Canada, with several provincial governments: Novia Scotia, New Brunswick, Manitoba and Prince Edward Island mounting legal challenges to keep him out.