At last month's COP17 climate-change negotiations in Durban, South Africa, Brazilian president Dilma Rousseff called for renewal of the Kyoto Protocol's binding targets for reducing greenhouse-gas emissions. We look to her to reaffirm Brazil's commitment to sustainable development by vetoing the proposed changes to the country's Forest Code when it comes before the Brazilian National Assembly for ratification in March.

The Senate has already approved revisions to the code, which would provide amnesty for previously illegal forest clearance and undermine efforts to limit deforestation.

Brazil should be setting an example as a green economy, particularly as it will be hosting the Rio+20 conference this year — the twentieth anniversary of the 1992 United Nations Conference on Environment and Development.

The adverse environmental effects that would be generated by the Forest Code revisions threaten to be made worse by the country's poor record for enforcing environmental law. For example, appeals against fines for environmental crimes are almost always successful (see go.nature.com/2xvs2o), amounting to nearly US$8 billion in unpaid penalties between 2005 and 2010.

Brazil's forestry regulations must be tailored to ensure the protection of forests alongside sustainable development. The new Forest Code would do neither.