My latest column for The Week is up. In it, I speculate about the likely effects of making community college free – assuming that the administration’s plan is enacted, and actually works as it is intended:

If the administration program succeeds, and participating community colleges offer more programs eligible for transfer to four-year institutions — tuition-free to all comers — then that option will become much more attractive for this sort of student [the marginal student barely able to afford to attend a four-year degree program]. Community college enrollment may well grow — but a large fraction of that growth may come from students who might otherwise have gone directly to a four-year institution.

What effect might that have, in turn, on those four-year institutions? All else being equal, one would assume that, if a supplier enters the market with a free product or service that is of acceptable quality, other market participants will respond either by focusing on a more quality-oriented market segment (willing and able to pay a premium for a premium product), or by exiting the market entirely.

If the administration’s proposal succeeds, for-profit colleges will have a harder time staying in business; it’s hard to compete with free. But it is equally reasonable to assume that four-year public institutions, perpetually strapped for funds, will decline to compete to keep those students most attracted by a fully transferable two-year degree. Rationally, they will reorient their own “business models” around a higher percentage of transfer students, with a higher percentage of non-transfer students being either ineligible for significant financial assistance, or of distinctly higher academic standing.

This is, of course, speculative – the plan is not going to be passed by this Congress, and if it were enacted it might not work as intended. I’m trying to tease out what the likely effects would be if it did work as intended – if the law passed, states eagerly signed up, and community colleges responded to incentives to restructure their programs to meet the eligibility criteria.

To be clear, it’s not obvious to me that a restructuring of community colleges to be more academically serious would be a bad thing, if the goal is to make higher education cheaper without sacrificing quality. But if the goal is to enable people to go to college who currently do not, I wonder whether the proposal will be that effective. Poor students, after all, are frequently attending community colleges for free now. And even if they benefit from the elimination of tuition, the eligibility criteria could inadvertently make it harder for them to remain enrolled.

Some folks have worried that community colleges will engage in rampant grade inflation to keep their graduation rates up (and thus remain eligible for subsidies). That could happen – but the requirement that credits be readily transferable to a four-year institution might prevent that eventuality. But another way to keep graduation rates up is to “fire” or “manage out” failing students, a process observed at many charter schools. The administration proposal includes money for remediation – but high-performing charter schools frequently do the same. Who knows where the bulk of the incentives will ultimately lie?

In any event, I concluded the piece with a throwaway line about the “class divide” running through the student body in higher education, and I want to complicate that view slightly. It is entirely likely that a poorer student, struggling to stay financially afloat at State U, might be better off spending two or three years at a community college and then transferring to State U. I mean that not just in financial terms but in social terms – at the community college she would be around more people like her, and when she transferred to State U she might be better prepared, socially, to handle this novel social environment. The class divide already runs through State U, and runs pretty deep.

But I do think it would change State U if the pool of poorer first-year students shrank significantly, particularly if state governments responded by reorienting their budgets to treat community colleges as the “proper” academic path for poorer students. And I also worry about the position of remedial students at community colleges if the college mission is re-oriented around transfer students.

To be clear: I’m not ultimately making an argument against the proposal, either against making community college free or against the eligibility criteria. I’m just teasing out possible unintended effects. Other proposals would undoubtedly have different unintended effects. Policy is rarely about finding a program with no downsides or unintended effects; it’s about finding one that is on-balance worthwhile, and being aware of those possible downsides so they can be mitigated.