Beacon Hill gravy train ready for boarding . . .

It was Christmas in February for Massachusetts senators, who on Thursday earmarked a $3.5 billion capital spending bill to within an inch of its legislative life. Of the 175 amendments offered by individual senators, requesting a pledge of public funds for everything from rail trails to theater restorations in their districts, only eight were rejected. (About 20 were withdrawn.)

That’s on top of the dozens of local projects that some favored lawmakers were already lucky enough to see baked into the original draft of the bill.

We could probably summon some outrage if this weren’t largely an exercise in fiscal public relations. Reps and senators enumerate their spending priorities in borrowing bills — but it is up to the governor to authorize the actual borrowing and spending.

So it’s effectively a legislative wish list. And many of the projects are indeed worthy — repairs to crumbling courthouses, for example, and improvements to campus facilities at public colleges and universities. Senior centers and public safety buildings and library repairs.

But the perennial question is precisely how some of these projects find their way into the legislation. What discussions take place in the back rooms that ensure Northampton gets an earmark for fixing up the local county fairground, for example — or how Danvers gets a special $3 million consideration to renovate the local food pantry.

And how do we know the discussions are in the back room? Because there is barely a word of floor debate on these measures.

One exception was the discussion about a $3 million set-aside to conduct an environmental impact study of a possible rail link between North and South stations in Boston — before the Baker administration’s review of the feasibility of that project has even been completed. For what it’s worth, the “discussion” amounted to a few sentences from the amendment’s Senate sponsor.

For lawmakers in an election year these earmarks represent valuable political currency. If only the taxpayers who make it all possible could be enlightened as to how the decisions are really made.