Judge's final actions key to federal charge for his murder

The actions and motivations of U.S. District Court Judge John Roll just before he was shot dead at Rep. Gabrielle Giffords's campaign event in Tucson on Saturday are important for the public narrative about the tragedy, but they're also vital to the federal criminal charge for his murder.

The criminal complaint federal prosecutors filed Sunday against the alleged shooter, Jared Loughner, goes to some lengths to demonstrate that Roll didn't show up at the Giffords event just to say hello to the congresswoman, or on some whim after attending mass, as reports Saturday suggested. That storyline was fueled by Pima County Sheriff Clarence Dupnik, who said "because [Roll] knows Gabrielle very well, [he] came around the corner to say hi. Unfortunately he was in the wrong place at the wrong time."

By contrast, FBI agent Tony Taylor argues that Roll was at the event to talk to Giffords about ongoing problems related to a surge in the federal judicial caseload in Arizona--a problem which the judge has attributed to a boost in the number of federal agents sent to the area to address immigration and border-related crime.

Under federal law, the murder or attempted murder of a U.S. official, such as a judge, is only considered a federal crime if committed "while such officer or employee is engaged in or on account of the performance of official duties." In other words, if Roll simply stopped by the event to greet Giffords, who he's said to have been friendly with, or due to idle curiosity about what was happening there, his killing probably wouldn't be a federal offense.

Prosecutors are so intent on showing that Roll was on official business that they rely on triple-hearsay to make the case in their complaint. Taylor says Giffords aide Ron Barber, who was seriously wounded in the attack, gave details about Roll's attendance at the event to Giffords's chief of staff Pia Carusone, who in turn told U.S. Marshal David Gonzales, who shared the info with Taylor. (Such hearsay probably wouldn't be permitted at a trial, but is fairly common in an agent's sworn decalation like the one filed Sunday.)

"Judge Roll attended the event and sought to speak to Congresswoman Giffords, and spoke with Mr. Barber about issues about the volume of federal cases in the District of Arizona; Judge Roll expressed his appreciation to Mr. Barber for the help and support Congresswoman Giffords had given," Taylor wrote, citing the triple-hearsay account. It's not clear if Roll ever talked to Giffords at the event Saturday.

Taylor also says Roll was told of the Giffords event by phone on Friday, knocking down the idea that he saw a sign or otherwise stumbled on the event on Saturday. And the FBI agent says video shows Roll "speaking for several minutes with Mr. Barber," which tends to suggest that the judge's visit wasn't purely social.

Of course, Roll's murder, like that of anyone killed at the event on Saturday, can also be prosecuted under state law. But it looks for now like the local prosecutors will take a back seat while the federal prosecution goes forward. The state can pursue its case after the feds are done. That is especially likely if the federal case were to end in a way some might consider unsatisfactory, such as an acquittal by reason of insanity or a sentence of life rather than the death penalty.

The presence or absence of the charge against Roll in the federal case probably won't make much difference in the punishment for Loughner stemming from the federal case. The killing of Giffords aide Gabriel Zimmerman would appear to make the federal case death penalty eligible, even if prosecutors have trouble proving beyond a reasonable doubt that Roll was "engaged in...official duties" at the time of his killing.