What will be the fate of Lord Saatchi's bill?

Today's main event in the House of Lords is the final helping of detailed consideration of Lord Saatchi's Medical Innovation Bill, which would give medical practitioners more flexibility to try new treatments on seriously ill patients.

His aim is to loosen what he clearly regards as the stultifying effect of the current law of clinical negligence on responsible medical innovation - and he seems to have government support.

Others are not impressed. In a little noticed adjournment debate on Tuesday, the new Chair of the Health Select Committee, Sarah Wollaston, fired off a formidable broadside against the Saatchi Bill.

Today there are 15 amendments to be considered at report stage, including from the fertility expert Lord Winston, the Labour front-bencher Lord Hunt of King's Heath and several from Lord Saatchi himself (this last is not at all unusual - the promoters of bills, including ministers, often bring in amendments to respond to points raised in earlier debates).

But what happens then? The bill may well get a third reading at some point in the new year, but it must also get through the Commons to become law. There's not much debating time available, so I suspect the most likely way for this to be achieved is for it to get a formal second reading, allowing it to be sent off to committee stage without debate.

Essentially, this process relies on its opponents not noticing.

What happens is this: Lords private members' bills carry no automatic priority entitling them to be debated in the Commons, so they're just added to a long list of bills, including such parliamentary pond-life as presentation bills and ten minute rule bills, at the far end of a long list of bills to be debated on a Friday sitting.

Typically there will be 20 plus bills on the Order Paper, and only the first three or four have any prospect of being debated. The titles of the remainder are read out by the Clerk at close of play, and each is greeted with the ritual shout of "object," usually from a government whip.

But if for any reason that shout is not shouted, the bill in question is deemed to have had a formal second reading and goes off to committee for detailed scrutiny. (A bill to exempt MPs' expenses claims from Freedom of Information legislation was once slipped through in this way, only to implode when no peer could be found with a high enough embarrassment threshold to take it through the Lords.)

The point is that the "object" usually comes from a whip, but doesn't have to; any MP can object and so prevent the bill moving to committee - and I'm told Lord Saatchi's opponents are alert to this possibility and will be present to should the fatal word.

So the best he may be able to achieve in this Parliament is to get a well-honed bill through the Lords, ready to be picked up by some sympathetic MP in the post-election Commons. (An earlier incarnation of the Saatchi bill was presented last year by the Conservative Michael Ellis, but didn't get through).

The same, incidentally, is probably true of Lord Falconer's Assisted Dying Bill. That, too, may clear the Lords but make no progress in the Commons before the election. So again, MPs who win a high place in the 2014-15 ballot for debating time to bring in a private member's bill can expect plenty of phone calls.