Compassionate Access, Research Expansion, and Respect States Act of 2017 or the CARERS Act of 2017 This bill amends the Controlled Substances Act to provide that the Act's regulatory controls and administrative, civil, and criminal penalties do not apply to a person who produces, possesses, distributes, dispenses, administers, tests, recommends, or delivers medical marijuana in compliance with state law. The bill also: excludes "cannabidiol" (CBD) from the definition of "marijuana"; limits the concentration of delta-9-tetrahydrocannabinol (THC) in CBD to 0.3 percent on a dry weight basis; and deems marijuana grown or processed to make CBD, in accordance with state law, to comply with the THC concentration limit unless the Drug Enforcement Administration (DEA) determines state law to be unreasonable. The bill directs the Department of Health and Human Services (HHS) to terminate the Public Health Service's interdisciplinary review process that is used to evaluate applications for medical marijuana research. The DEA must license manufacturers and distributors of marijuana for medical research; HHS must register practitioners to conduct research; and the Department of Veterans Affairs (VA) must authorize VA health care providers to provide recommendations and opinions to veterans regarding participation in their states' marijuana programs.