From the summary: "Eligible veterans are entitled to receive military honors at their funerals. Federal law, enacted in 1999 (P.L. 105-261) and amended in 2000 (P.L. 106-65) provides that each eligible veteran shall be provided, at minimum, (1) a two-person funeral honors detail, (2) the playing of taps, and (3) the folding and presentation of a U.S. flag to the family. The Department of Veterans Affairs (VA) issues these honors at no cost to the veteran's family. These honors can be augmented to include color guards, pallbearers, and firing parties provided either by the military or civilians in approved veterans or other organizations. Funeral honors at Arlington National Cemetery include additional elements according to the rank of the deceased. Persons involved in capital crimes are ineligible for military funeral honors. In 1997, Congress began prohibiting interment and inurnment in national cemeteries and military funeral honors for persons involved in federal or state capital crimes. In 2006, Congress passed a law (P.L. 109-461) ordering the cremated remains of a veteran who had been convicted of two counts of murder be removed from Arlington National Cemetery. In 2013, pursuant to the Supreme Court's decision in 'United States v. Windsor', same-sex spouses of eligible veterans became eligible for interment and inurnment in national cemeteries. Legislation enacted in 2016 (P.L. 114-158) permits civilians granted veterans status under federal law, such as Women's Air Force Service Pilots (WASPs), to be inurned in the Columbarium or Niche Wall at Arlington National Cemetery."
CRS Report for Congress, R44426
Federation of American Scientists: http://www.fas.org/sgp/crs/index.html