The country's historic 2016 peace deal with former FARC guerrillas closed a chapter on a half-century of armed conflict but also caused rapidly accelerating forest loss in remote regions of the country.
Colombia's new president, Ivan Duque, wants to weaken the deal, which he sees as "too lenient" on the fighters who once terrorized the country.
A swift victory in the Colombian Supreme Court could pave the way for further legal action around the world.
The FARC-backed presidential candidate Rodrigo Londoño pulled out of the race over health concerns, but his violent past had made his candidacy a divisive one.
After a major court decision protecting a peace agreement between rebel groups and the government, the future looks promising for Colombia, but the process is still far from over.
Last year, 200 environmentalists across 24 countries were murdered—up from 185 across 16 countries in 2015.