Donald Oswald, a former special agent in charge in Minneapolis, said in the letter mailed to Senate Judiciary Committee members that he felt morally compelled to share what he called Jones' "atrocious professional reputation" among Minnesota law enforcement. Oswald said he felt he could speak out because he has retired, while active law enforcement authorities might fear retaliation.
"When I learned on TV that Todd Jones had been nominated by the president for ATF director, I reacted physically ill to it and it bothered me for several days until I decided I had to do something, and I had to put this letter forward to reveal exactly what kind of a leader he is," Oswald said in an interview with The Associated Press.
Jones, currently acting director of the ATF, was unable to comment on Oswald's claims because his confirmation is pending before the Senate. But several people who have worked with Jones called him an outstanding leader who takes violent crime seriously.
A former Marine, Jones has been U.S. attorney for Minnesota since 2009. Obama announced in mid-January that he would nominate Jones to lead the ATF, an agency that hasn't had a permanent director for six years.
Oswald's letter, which he provided to AP, accuses Jones of impeding federal prosecutions of gang, drug and gun laws. Oswald said Jones was instead "substantially motivated by personal political gain and not by doing what's in the best interest of the citizens he is sworn to protect."
Oswald ran the Minneapolis FBI office from spring 2011 to spring 2012 before retiring to practice law in south Florida. During that time, he wrote, agents and others believed Jones did not support violent cases. Oswald said when complaints were raised, Jones "reacted defensively and often spoke to us disrespectfully, and occasionally with disdain." Federal agencies contacted by the AP declined to comment for this story. The Minneapolis FBI office noted Oswald is now a private citizen and his views do not reflect the views of the bureau.
Sen. Charles Grassley, the Judiciary Committee's senior Republican, issued a statement calling Oswald's allegations "very disturbing" and said they would be examined closely.
Oswald said Department of Justice statistics show Jones' office charged 329 defendants in fiscal year 2012, down 40 percent from the 546 people charged in fiscal year 2011. In violent crime and gun cases, 80 people were charged last year compared with 125 in fiscal year 2011.
Jeanne Cooney, the U.S. attorney's office spokeswoman, said the office has shifted focus because crime has shifted.
"This office takes fewer gun and violent crime cases than it had previously because we now take the worst of the worst offenders, leaving the others to be prosecuted at the state level," she said. "And they are very effectively prosecuted there."
Cooney said that allows the federal prosecutor's office to use resources on larger cases. For example, she said, violent crime prosecutions have indeed fallen in number, but sentences are higher. For fiscal year 2012, almost three-quarters of all offenders sentenced to prison for gun or other violent crimes were ordered to serve five years or more, compared to about half of offenders before Jones.
Ralph Boelter, the special agent in charge of the FBI's Minneapolis office from 2007 through 2011, said he had a good relationship with Jones.
"We were in sync," Boelter said. "Now did we agree on everything? No, that would not be reality ... because the issues you encounter together are complex." But Boelter said he didn't experience anything like the behavior Oswald described. He said when he had an issue, Jones was "attentive to it, he was sensitive to it and he responded to it."
Boelter said Jones stood strongly with him in 2009 when Minneapolis found itself in the middle of what Boelter called the FBI's highest national security priority at the time—the phenomenon of young Somali men leaving Minneapolis to join the al-Qaida-linked terrorist group al-Shabab in Somalia. As the investigation was moving at a dizzying pace, Boelter began reaching out to the Somali community to build relationships.
"I needed a partner," Boelter said. "We were right there on the front lines, and Todd was right there with me."
Hennepin County Attorney Mike Freeman also spoke in defense of Jones.
In response to a spike in homicides in Minneapolis in early 2010, Jones, Freeman and other local officials launched a program designed to assess whether violent gun cases should be prosecuted in federal court, where penalties can be more severe. Cooney said Jones' office has handled 18 cases under that initiative, and that in fiscal 2012, the office saw a dramatic increase in the length of sentences for violent crimes.
Freeman said a "healthy tension" between prosecutors and law enforcement is natural, because the two don't always agree whether there's enough evidence to support a case.
Former Minneapolis Police Chief Tim Dolan, who retired in 2012, said in an email to the AP that U.S. attorneys around the country are faced with changing priorities, which can be frustrating at times to police who want to put gang members away.
"Homeland Security and White Collar Crime are their top two priorities, and it is understandable big picture wise why that is the case," Dolan said.