LONDON (AP) — A proposed bill to allow terminally ill adults in England and Wales to choose to end their lives failed Friday as parliamentary time ran out following an effective filibuster by unelected lawmakers in the revising chamber that blocked the will of elected members.

Though the Terminally Ill Adults (End of Life) Bill was passed by the House of Commons last June, the House of Lords talked it out since then, stoking widespread criticism that it had overstepped the mark.

Proponents of what has been termed “assisted dying” — sometimes referred to as “assisted suicide” — hoped it would mark the biggest change to social policy in the U.K. since abortion was partially legalized in 1967. The intention was to put an end to the practice of those near the end of their lives from going to other countries, such as Switzerland, for an assisted death.

The bill had proposed allowing adults in England and Wales, with fewer than six months to live, to apply for an assisted death subject to the approval of two doctors and an expert panel.

But opponents in the House of Lords managed to hold up its passing by filing more than 1,200 amendments on a range of concerns, including the potential coercion of vulnerable people and a lack of safeguards for those with disabilities.

“The House of Lords scrutiny exposed this bill as ‘skeleton legislation’ riddled with gaping holes,” said Gordon Macdonald from the Care Not Killing campaign group which is opposed to a change in the law. “It is now clear that this bill was both unsafe and unworkable.”

The number of amendments is believed to be a record high for a piece of legislation that was brought forward by a backbencher rather than by the government. These so-called private members’ bills can only be debated on a Friday as the government largely controls the rest of the parliamentary timetable, thereby limiting the time available.