After leading the charge for a government shutdown to defund President Barack Obama’s health care law, freshman Sen. Ted Cruz, R-Texas, hasn’t shied away from the spotlight.

On Nov. 8, 2013, Cruz was a guest on t he Tonight Show with Jay Leno . Long before he got to the obligatory joke about reading Green Eggs & Ham during a lengthy Senate speech, he addressed gun policy.

"Do you target violent criminals, or do you try to take away the constitutional rights of law-abiding citizens?" Cruz said.

After the senator criticized Obama for focusing on the latter at the expense of the former, he praised predecessor George W. Bush’s efforts.

"Under President Bush, prosecution of gun crimes was 30 percent higher than it is under President Obama," Cruz said. "They’re not targeting bad guys."

We decided to see how the numbers differed under the two presidents.

Ways to read the data

Let’s break down the number of federal prosecutions by year. We’ll start with fiscal year 2002, since that represents Bush’s first full year in office. Fiscal year 2012 is the most recent year we have data for.

There are two different sets of statistics we can look at. Cruz’s spokeswoman referred us to the Transitional Records Access Clearinghouse, a Syracuse University data-gathering organization. This data tracks federal gun prosecutions by the lead, or most serious, charge.

On the other hand, the Department of Justice’s United States Attorney’s Office tracks all charges, a more inclusive category of prosecutions. Their data set includes everyone who was charged with a gun crime. The lead charge category only includes people whose most serious offense was gun-related, a distinction that omits thousands of charges each year.

Lead charges All charges 2002 7,948 10,634 2003 10,432 13,037 2004 11,015 12,962 2005 10,219 13,062 2006 9,652 12,479 2007 8,919 12,087 2008 8,484 11,974 2009 8,188 11,722 2010 7,614 11,421 2011 7,465 11,811 2012 7,774 11,728

Cruz’s spokeswoman also told us that Cruz’s claim didn’t take into account numbers for Bush’s entire term: He used 2004, the high-water mark for lead gun prosecutions during the time period, as his starting point.

We’re left with four ways to calculate the percent change:

• Lead charges from 2002 to 2012, which gives us a 2.2 percent decrease

• Lead charges from 2004 to 2012, which gives us a 29.4 percent decrease

• All charges from 2002 to 2012, which gives us a 10.3 percent increase

• All charges from 2005 (the high-water mark of this data set) to 2012, which gives us a 10.2 percent decrease

This makes clear how Cruz got his 30 percent decrease. However, that’s not the only, or necessarily the best, approach.

None other than TRAC’s co-director, Susan Long, told PolitiFact that her organization’s use of lead charges isn’t as comprehensive as using all charges. She also called Cruz’s 2004 start date misleading, since it amounts to cherry-picking.

The most reliable number may be the 10.3 percent increase in gun prosecutions between fiscal years 2002 and 2012. This rate actually indicates the trend moving in the opposite direction from what Cruz asserted.

Who’s responsible?

In addition to highlighting a numerical difference in federal gun crime prosecutions, Cruz specifically suggested that Obama’s policies are responsible for the decrease. But how much influence does the president really have on the issue?

Experts say: not much.

"The Bush administration was all over the map," Long said. "Those trends really are being driven by something other than presidential policy," since the peaks and valleys don’t coincide with presidential terms, she said.

As we’ve noted in a previous fact check, the president, as the head of the executive branch, can order changes to prosecutorial priorities. For instance, following the Newtown, Conn. school shooting in December 2012, Obama did call for the need to "maximize enforcement efforts to prevent gun violence and prosecute gun crime."

We don’t yet have data that reflects prosecutions in the aftermath of Newtown. But it’s important to note that Obama’s priorities are not the only factors at play in these decisions. Any presidential shift in policy must filter down to the attorney general, the Bureau of Alcohol, Tobacco, Firearms and Explosives field offices, and front-line attorneys, said Ronald Frandsen, grants administrator for the Regional Justice Information Service.

U.S. attorneys can decline to prosecute gun cases for a variety of reasons, as outlined by TRAC.

So Obama is responsible for setting the broad policy approach to gun prosecutions, but he isn’t micromanaging individual cases. Much of the decision-making occurs at a lower level.

Our ruling

Cruz said prosecution of gun crimes under the Bush administration was 30 percent higher than it is under Obama.

It’s possible to get a decline that big by cherry-picking the data, but the most inclusive method actually produces an increase. Cruz also overstates the role of the president in determining prosecution rates. We rate Cruz’s claim Mostly False.