John P. Smith Act (Sec. 3) This bill modifies the approval process under the National Environmental Policy Act (NEPA) for tribal transportation safety projects to categorically exclude qualifying projects from requirements to conduct environmental assessments and environmental impact statements. A tribal transportation safety project is one that is eligible for assistance under the tribal transportation program and that: (1) corrects or improves a hazardous road location or feature, or (2) addresses a highway safety problem. The Department of the Interior must: (1) review existing Federal Highway Administration categorical exclusions to determine applicability to tribal transportation program projects, and (2) identify tribal transportation safety projects that meet general categorical exclusion requirements. Interior must establish categorical exclusions for tribal projects consistent with its findings. The bill prescribes requirements for the expedited review and approval of tribal transportation safety projects under NEPA or other federal laws. (Sec. 4) Interior must enter into five-year programmatic agreements with Indian tribes that establish efficient administrative procedures for carrying out environmental reviews for tribal transportation program projects. An agreement may allow a tribe to determine whether a project is categorically excluded from the preparation of an environmental assessment or impact statement under NEPA.