A new FEDEA Note, published this Monday and to which Demócrata has had access, shows that many interventions on active rental contracts alleviate a visible problem today, but reduce supply and tomorrow harden access to housing for the most fragile households.
The new issue, titled: “The paradox of contractual protection”, whose author is the economist Benito Arruñada, analyzes a central mechanism of housing political economy: when judges and legislators rewrite already signed contracts or weaken their enforcement to protect one of the current parties, they usually harm precisely those who, with similar or greater fragility, will try to contract later. In residential rental, this effect falls especially on the most vulnerable future tenants.
The thesis of the Note is that the main conflict does not occur between owners and tenants, but between current and future tenants. The benefit for whoever already has a contract is visible, immediate, and politically profitable. The cost for whoever has not yet contracted appears later and almost without a face: less supply, harsher filters, more guarantees demanded, and more difficulty of access.
#housing 🔴 New #ApuntesFedea by @BenitoArrunada 🔄 The paradox of contractual protection: Protecting today's weak excludes tomorrow's weak 👇 https://t.co/PMf9RN7voZ
— Fedea (@socialfedea) April 13, 2026
📄 Doc ➡️ https://t.co/8ah04qCdDe
The case of Catalonia
Spain offers a particularly clear case. Arruñada maintains that since 2020 a known sequence has been reinforced: relief is granted to contracts in force, the cost is shifted off-budget, and tomorrow's rental market is left to pay for it. In Catalonia, the first community to apply the new regime of Law 12/2023 and to declare itself a stressed area, the number of contracts fell in 2024 by 10.8% compared to 2023 —14.9% in Barcelona city—, while the average annual rent increased by 1.1% in Catalonia as a whole and by 1.0% in Barcelona, according to the official Incasòl deposit registry cited in the study. The available evidence also points to a clearer effect on the contraction of supply and contracting than on price containment.
The document does not argue that all contractual protection is harmful. It distinguishes between guarantees that facilitate ex ante contracting and imperative and retroactive rules that rewrite already signed contracts or hinder their fulfillment. The problem arises when an attempt is made to solve a structural problem by decree-law or through provisional rules with immediate effect and its cost is made to fall on one of the parties to the private contract. That formula allows for displaying visible relief from today, but transfers legal uncertainty and supply contraction to the market.
Public aid versus the cost to owners
Hence the practical rule proposed by the Note: if society wants to help a vulnerable household, it must do so with public funds and not by transferring the cost to specific owners. Emergency aid, in that logic, must be personal, temporary, and conditional. Ordinary contracting, on the other hand, requires general and prospective rules, rapid execution, and strict limits on retroactivity.
The work also emphasizes that the other major task is in supply. Land, licenses, administrative times, judicial times, and mobility taxation continue to hinder the expansion of the rental stock. As long as this bottleneck persists, any attempt to distribute scarcity by decree will tend to make access more difficult for those entering the market in a worse position.
In summary, the Note argues that many housing policies do not fail due to bad intention, but due to a political balance that rewards immediate relief and hides its future costs. In this area, protecting today's weak at the expense of the contract can mean excluding tomorrow's weak from the market.