Veterans Treatment Court Improvement Act of 2018 This bill requires the Department of Veterans Affairs (VA) to hire at least 50 Veterans Justice Outreach Specialists, place each one at an eligible VA medical center, and ensure that each one serves as part of a justice team in a veterans treatment court or other veteran-focused court. An eligible VA medical center is one that: complies with all VA guidelines and regulations for placement of a specialist; works with a veteran with active, ongoing, or recent contact with some component of a local criminal justice system; maintains an affiliation with one or more veterans treatment courts or other veteran-focused courts; and either routinely provides specialists, or establishes a VA-approved plan to provide specialists, to serve as part of a justice team in such a court. The VA shall prioritize the placement of specialists at eligible VA medical centers that have an affiliation with such a court that: