With continued forest loss in tropical regions, it is important to understand whether and how public policies influence deforestation rates. One potentially important policy is Brazil’s “Native Vegetation Protection Law” (NVPL), passed in 2012 and popularly known as the New Forest Code. The goal of the law is to prevent forest loss; however, its success at maintaining forest is unclear. We analyze the effectiveness of the law in the state of Amazonas, Brazil by measuring forest loss in 2009 and 2012, pre implementation of the new vegetation protection law (NVPL) and comparing this to loss that occurred in 2015 and 2018, post-NVPL, in Settlement Projects (SP) affected by NVPL and Indigenous Lands (IL) and State/National Forests which were not under the mandate of the NVPL. We used these last two categories as Control Areas. Forest loss was greatest in SP during both time periods relative to two other categories considered. Implementation of the NVPL did not reduce overall deforestation in SPs. However, it did keep deforestation within the 20% limit set by NVPL in 31 of 35 SPs surveyed. In addition, forest cover decreased in only a few SPs. The variable with the strongest influence on deforestation within SP and IL was intensity of human land use in surrounding areas. We also found that IL and CU categories play an important role in maintaining overall forest cover.