Els Borst, a former health minister who drafted the Netherlands' 2002 law permitting euthanasia, has been found dead in her garage, police said.
The 81-year-old's body was discovered by friends on Monday evening, Utrecht police said.
Forensic investigators, after working through the night, have ruled out a natural cause of death. Police expect a post-mortem examination to show whether her death was the result of "an accident or possibly a crime", they said in a statement.
She was seen in good spirits as recently as Saturday, at a function of her centrist D66 political party.
Ms Borst was a medical academic who served as health minister from 1994 to 2002.
The country's euthanasia law, which codified longstanding practice, allows euthanasia when a terminally ill person requests it, is suffering unbearably and has no chance of recovery. Two doctors must agree.
Prime minister Mark Rutte praised Ms Borst as "a wise professional, with clear and considered standpoints, who stood her ground".
"She won people over with her openness, mildness and honesty," he said.
Ms Borst's viewpoints were often at odds with those of religious groups but enjoyed the approval of most Dutch voters.
Trying to prevent a measles epidemic in the Dutch Calvinist bible belt last year, she wrote an opinion piece in newspaper Algemeen Dagblad asking pastors and churchgoers to get vaccinated.
"If everything is God's will, then so is the invention of the vaccine, just like the seatbelt," she said.
In an interview with newspaper NRC in 2001 she acknowledged she was not opposed in principle to a suicide pill for "very aged people who are finished with life".
But "we have to have a thorough societal discussion of this subject", she told the paper.
Ms Borst, one of the first Dutchwomen to reach high political office, held the title of "minister of state" - one of a handful of former leaders given diplomatic passports who are allowed to represent the country on the international stage.
She is survived by three children.