Death penalty for murder; treason Saint Vincent and the Grenadines 1995 n/a Death penalty for murder; treason Suriname 1982 2015[54] Abolished 2015. Trinidad and Tobago 1999 n/a Death penalty for murder; treason[128] United States 2017[129] 20 n/a Methods vary by state, federal, and military policy, but include lethal injection, hanging, firing squad, the electric chair, and the gas chamber.