Juvenile Justice Accountability and Improvement Act of 2007 - Requires states to enact laws and adopt policies to grant child offenders who are under a life sentence a meaningful opportunity for parole at least once during their first 15 years of incarceration and at least once every three years thereafter. Defines "child offender who is under a life sentence" as an individual who is convicted of a criminal offense before attaining the age of 18 and sentenced to a term of natural life or its functional equivalent in years.
Requires the Attorney General to: (1) establish and implement a system of early release for each child offender who is under a life sentence in a federal prison; and (2) award grants to states to improve legal representation and other services for child defendants charged with an offense carrying a possible sentence of life in prison.