Will Keir Starmer legalise assisted dying?
Prime ministers often have to deal with matters of life and death, but perhaps few are quite so discernable as the matter of assisted dying.
This complex and ethically fraught issue has been debated several times by parliament before.
Now, the debate is set to return again and the question is whether the prime minister intends to wade into it.
Lord Falconer, who achieved some success with an assisted dying bill in the House of Lords in 2014, will make a second attempt to legalise it when he presents another bill on Friday.
If it becomes law, it will allow terminally ill people with less than six months left to live to seek an assisted death, or what others call assisted suicide.
The bill progressed through the Lords in 2014 but didn't make progress in the Commons before the 2015 election was called.
What could be different this time, is that we now have a prime minister who himself favours the legalisation of assisted dying.
We filmed as Sir Keir Starmer told campaigner Dame Esther Rantzen in March that he'll make time to debate the matter in parliament.
It is something he cares deeply about, having worked on the details of the current law as director of public prosecutions and personally witnessed the effects of debilitating illnesses in his own family.
He would favour a free vote, where MPs are allowed to vote with their consciences, rather than following any party orders.
So, is this his opportunity to deliver on his promise?
In a word, no.
My understanding is that the government would much rather wait for a bill to be presented to the Commons, rather than get involved in one originating in the Lords.
The practical issue is that if Lord Falconer's bill is allowed to pass by peers, it then goes to the back of the queue in the Commons.
Without the government grabbing hold of the bill and making time for it, its progress would stall.
However, I anticipate that the prime minister will not choose to implement this intervention.
Why not? Because he may fear that it sets a difficult precedent if his government picks and chooses which Lords bills it wishes the Commons to focus on.
You can imagine the cry from other peers and campaign groups wanting Starmer to champion their issues too.
A less tricky scenario would be for an MP to propose an assisted dying bill in the Commons.
This is possible, with a ballot taking place in September to decide which MPs will get to bring private members' bills (PMBs) forward.
There are plenty of MPs with an interest in this area, but they'll need luck on their side to come near the top of the ballot and have any chance of success.
In that scenario, I would anticipate Starmer's government giving time (which is rarely on the side of PMBs) for a debate.
Subscribe free to our weekly newsletter for exclusive and original coverage from ITV News. Direct to your inbox every Friday morning.
It would be very difficult after all for him to row back from his pledge to Dame Esther Rantzen.
All this isn't to say that Lord Falconer's bill is unimportant.
The debate itself will rocket assisted dying back up the parliamentary agenda and spark passionate discussion between those who believe it offers hope and those who believe it proffers danger.
The arguments for and against are well-rehearsed, but no less passionate than they have ever been.
This particular bill is unlikely to resolve them.
Have you heard our new podcast Talking Politics? Tom, Robert and Anushka dig into the biggest issues dominating the political agenda in every episode…