As a 501(c)(3) organization, Earthjustice is not legally allowed to take part in electoral work or endorse candidates. 501(c)(3) organizations are nonprofits serving charitable, religious, or educational purposes. They are permitted to engage in a limited amount of lobbying, advocacy, or political activity, but they are prohibited from taking part in electoral activities. Donations to a 501(c)(3) are tax-deductible.
Earthjustice Action is a separate but affiliated organization launched in 2017. As a 501(c)(4) organization, Earthjustice Action is legally permitted to engage in a broader range of activities than Earthjustice, including lobbying beyond 501(c)(3) limits and electoral activities. Donations to Earthjustice Action, and 501(c)(4)s generally, are not tax-deductible.
You can read more about the differences between Earthjustice and Earthjustice Action here.