MacDonald, a member of the Independent Lothians party, said it should not be a crime to assist the suicide of someone who is suffering from a condition and wants to die.
MacDonald intends to publish a consultation paper by the end of November and will include a wide spectrum of people to discuss the issue.
The detailed proposals of the Bill will be determined by the responses to her consultation paper.
MacDonald, who lives with Parkinson's disease said:
"The politicians have run a mile from this, but they cannot continue to run. I'm not telling them what they have to believe, we all have our own values and beliefs, but they owe it to their constituents to debate the matter."
MacDonald says she has been moved by the case of Dan James (23) a former Rugby player who was paralysed by a training accident and recently died in Switzerland by assisted suicide with his parents accompanying to his death.
MacDonald's announcement specifically followed the decision by the High Court not to guarantee that Debbie Purdy's husband, Omar Puente, would be free from prosecution if he would assist her suicide in Switzerland at the Dignitas Clinic.
The Scottish people need to be aware of how legalizing assisted suicide specifically threatens the lives of people with disabilities and the other vulnerable people in Scotland.
Legalizing assisted suicide creates an inequality in the healthcare system because it allows some people to receive death as the treatment for their condition and others to receive good physical, psychological and social care for the same condition.
It also introduces subtle and overt pressures on people who are living in the most vulnerable time of their lives. Social and economic pressures will often coerce people to "choose" death because they feel they have no other "choice" or to fulfill the wishes of their loved ones or caregivers of the "burden" of care.
Link to the article from the Edinborough Evening News: