Most Americans, 74 percent, also back the decision to try Tsarnaev in the federal court system instead of a military tribunal.
Federal prosecutors in Boston charged Tsarnaev more than a week ago with using a weapon of mass destruction and malicious destruction of property, counts that could bring him the death penalty.
Under the law, he could not be tried in a military commission because he is a U.S. citizen. Some Republican lawmakers had argued, however, that Tsarnaev should have been declared an “enemy combatant,” allowing him to be interrogated for as long as possible, without being read his Miranda rights, before being turned over to the federal judicial system.
Majority support for the federal approach crosses party lines, with 80 percent of Democrats, 73 percent of independents and 72 percent of Republicans saying they back a civilian trial. However, Democrats are by far the most apt to support it “strongly.” Democrats are also the least likely to strongly support the use of the death penalty, although most of them do support it, at least somewhat.
The bigger divide on the death penalty is between whites and African Americans. While 75 percent of whites say they would back the use of the death penalty were Tsarnaev convicted, the support among African Americans barely goes past the midpoint: 52 percent of African Americans would support the death penalty, and 43 percent would oppose it.
Hispanics also are less likely than whites to support the death penalty in this instance: 62 percent would support it; 35 percent would oppose it.
The large gap between whites and blacks has probably more to do with the death penalty itself than this particular case. In a recent Washington Post Maryland poll, 63 percent of whites and only 37 percent of African Americans said they favor the death penalty for people convicted of murder.
This week, a federal magistrate in Boston said that, in addition to his public defenders, Tsarnaev would be represented by Judith Clarke, a renowned lawyer in death penalty cases whose clients have included Jared Loughner, who killed six people in the 2011 shooting that wounded then-Rep. Gabrielle Giffords (D-Ariz.), and Theodore J. Kaczynski, the Unabomber.
The new Washington Post-ABC News poll was conducted April 24 to 28 among a random national sample of 1,000 adults. The results have a margin of sampling error of plus or minus 3.5 percentage points.
Cohen is director of polling for Capital Insight, the independent polling group of Washington Post Media.