Leather manufacturing group JBS Couros has told The New York Times that it engaged directly with non-profit organisation the Sustainable Apparel Coalition (SAC) last year because it wanted to correct “misleading analyses” of leather in the Higg Materials Sustainability Index (MSI), the scoring system for fashion sustainability that the SAC set up in 2011, writes Leatherbiz.

As a result, an update of the Higg MSI recently gave a more sustainable score for leather from JBS than for the material in general. The index has provided similar updates for leather from at least two other groups, PrimeAsia and Sadesa, after they, too, supplied detailed information.

Many fashion brands use data from the Higg MSI to present their products as sustainable. There has been consistent criticism of the index, however, for using out-of-date and unrepresentative data to make natural materials, including leather, appear less sustainable than synthetic alternatives. The New York Times added its weight to the argument in a detailed article on June 12.

In response to the criticism, SAC vice-president, Jeremy Lardeau, told the newspaper: “We’re not actively pushing for the synthetic numbers to be low. We’re just collecting the data in one place.” The writer of the article, Pulitzer Prize-winner Hiroko Tabuchi, included detail from a formal complaint from the global leather industry in 2020 that the Higg’s general leather score was based on “out-of-date, unrepresentative, inaccurate and incomplete data.”

Ms Tabuchi also devoted substantial space to similar criticism from the global silk industry. She said silk’s unfavourable rating in the Higg MSI draws on a 2014 study by Oxford-based researchers of 100 silk farmers in a single state in India. “That study’s lead researcher, Miguel F. Astudillo, said he hadn’t known until recently that his work had been used by the Higg Index,” she wrote. Dr Astudillo told her his study of Indian silk was not representative of global production and that if people at the SAC had read the paper and the results, “they’d know it’s a stretch to use it for assessing silk in general”.

JBS Couros told Ms Tabuchi that it intends to continue to contribute data to the Higg MSI “to elevate the quality of technical information available on leather, benefiting the entire sector”.