Interim Conservative Leader Rona Ambrose says changes proposed by the Senate to the Liberal government's proposed new law on medically assisted dying are a sign of a bigger problem.

Senators voted 41-30 on Wednesday to amend Bill C-14, to allow suffering patients who are not near death to seek medical help to end their lives.

The change, if accepted, would delete a requirement that a person's natural death be reasonably foreseeable, removing the central pillar underpinning the legislation.

The amendment replaces the eligibility criteria in the bill with the much more permissive criteria set out in last year's landmark Supreme Court of Canada ruling, which struck down the ban on assisted dying.

That sets the Senate on a potential collision course with the government.

But Ambrose says it also circumvents the will of the elected House of Commons, just as she said the Supreme Court did in setting parameters around doctor assisted death.

"We have the courts making laws in this country and now we have an unelected Senate changing the laws of an elected House," Ambrose told a news conference Thursday.

"There's even a larger debate here, which I think is upsetting a lot of my constituents and a lot of people across the country."

Interim Conservative Leader Rona Ambrose says the unelected Senate should not be changing or amending laws like C-14 that were drafted by an elected House of Commons. 1:44

Justice Minister Jody Wilson-Raybould has signalled that the government is unlikely to accept such an amendment, saying a lot of work went into ensuring a balance between recognizing personal autonomy and protecting the vulnerable.

Ambrose agreed with Wilson-Raybould that the bill approved in the Commons and sent to the Senate strikes the right balance, although she actually voted against it.

The Senate is expected to continue debating the bill and voting on other amendments into next week.