The U.S. government will appeal the dismissal of a manslaughter case against five employees of the Blackwater private security firm, Vice President Joe Biden said Saturday.

During his visit to Iraq, Biden expressed "personal regret" for the shooting and said the Obama administration was disappointed by the dismissal.

"A dismissal is not an acquittal," he said, according to the Associated Press.

More from the AP:

Biden's announcement after a meeting with Iraqi President Jalal Talabani shows just how diplomatically sensitive the incident remains nearly three years later. A lawyer for one guard, noting that word of the intended appeal came in Iraq, accused the Obama administration of political expediency and the U.S. was pursuing an innocent man, rather than justice.

Blackwater security contractors were guarding U.S. diplomats when the guards opened fire in Nisoor Square, a crowded Baghdad intersection, on Sept. 16, 2007. Seventeen people were killed, including women and children, in a shooting that inflamed anti-American sentiment in Iraqi.

[...]

The U.S. rebuffed Iraqi demands that the U.S. contractors face trial in Iraqi courts. After a lengthy investigation, U.S. prosecutors charged five of the contractors with manslaughter and took a guilty plea from a sixth.

But the case fell apart when a federal trial judge in Washington, Ricardo Urbina, said in a Dec. 31 ruling that the Justice Department mishandled evidence and violated the guards' constitutional rights. Prosecutors now face difficult odds getting an appeals court to reinstate the case.

The dismissal outraged many Iraqis, who said it showed the Americans considered themselves above the law. The Iraqi government began collecting signatures for a class-action lawsuit from victims who were wounded or lost relatives.

A lawyer for Blackwater guard Donald Ball, a former U.S. Marine from West Valley City, Utah, sharply criticized the U.S. government's planned appeal.

"By announcing this decision in Iraq, through an elected official, the United States makes clear it has decided to do what is politically expedient, rather than what is just based on Judge Urbinas unshakable findings that the prosecutors engaged in gross misconduct and intentionally violated Mr. Ball's constitutional rights," attorney Steven McCool said in a statement.