Zara has a strict policy against using materials that are obtained from unethical sources. It is difficult to determine whether Zara's leather shorts are ethical without more specific information about the materials and production methods used. However, Zara is a brand that has been criticized in the past for its labor practices and environmental impact. It is essential to do your own research and consider your own values when making purchasing decisions. You may also consider looking for alternative brands that prioritize ethical and sustainable practices in their production processes.