CHICAGO (CBS) — U.S. Attorney General William Barr was in Chicago Wednesday touting success with Operation Legend to reduce crime in the city.

But just one day earlier, police Supt. David Brown was the one taking credit for cutting crime. So who, or what, really gets the credit for making Chicago safer?

Public safety is stated as a top priority for Mayor Lori Lightfoot and President Donald Trump’s administrations – which is why both would want to take credit for any violence reduction.

And of course, politics are at play too.

This year has been one of the most violent years in Chicago’s history. But violent crime is trending downward now, and Barr credits a federal crime-fighting effort called Operation Legend for that decline.

“The bottom line is that Operation Legend has played a critical role in cutting Chicago’s murder rate roughly in half since before the operation,” Barr said.

The joint federal, state, and local law enforcement operation launched on July 22.

“Over the first five weeks of Operation Legend in Chicago, murders dropped by 50 percent over the previous five weeks,” Barr said.

The numbers back that up. But just a day ago, Supt. Brown took credit.

“So seven weeks of the reorganization that I put in place under my tenure has resulted in a 50 percent reduction in murders,” he said Tuesday.

Enter Mayor Lightfoot.

“What I’m saying to you is we started seeing that reduction even before the federal resources were even here in Chicago,” the mayor said.

There may be splitting of hairs on all sides. But one thing is certain – murders are still significantly up this year. So far, there have been 524 homicides in Chicago this year, compared with 345 murders at this point last year.

“Nobody should be taking a victory lap,” Mayor Lightfoot said.

The mayor, who was not invited to Barr’s news conference, had Supt. Brown give Barr a letter. It outlined other specific ways the federal government could help reduce Chicago’s violence, such as universal background checks for gun purchases.

Meanwhile, Barr sidestepped questions about President Trump’s criticism of Mayor Lightfoot’s leadership.

“I’m not going to comment on that,” Barr said.

Barr focused instead on the administration’s message of law and order. The mayor said politics were the reason Supt. Brown did not attend the news conference, because city leaders would never be used as a prop to help President Trump’s reelection.

Barr and U.S. Attorney John Lausch said 400 federal agents from various agencies were funneled to Operation Legend in Chicago.

Both Barr and the mayor credit a partnership for any success. But it will be some time before we know if the violent crime drop lasts, or if the decline is temporary.