Donald Trump promised in 2015 that one of the "first things" he would do if elected president would be an executive order to impose the death penalty for people who kill police officers. He renewed his call for it in 2018, but we still haven't seen any movement to turn this campaign pledge into policy.

One explanation for that might be the slew of legal barriers.

Experts say that the president doesn't have the power to create penal laws by executive order, and the Supreme Court ruled in Woodson vs. North Carolina in 1976 that mandatory death sentences are unconstitutional.

Sheri Johnson, a law professor at Cornell University, said that because a president can't impose the death penalty on Americans by executive order, Congress would have to pass a statute to do so, and any such statue would face a constitutional challenge that it exceeds the power of the federal government. 

"Moreover, it is conservative justices who are most hesitant to expand federal powers, so it is hard to see where the support would come from," Johnson wrote in an email. 

Then there's the fact that the death penalty is largely a state issue. (Capital punishment is currently authorized in 28 states.)

The death penalty is legal at the federal level, and the U.S. government announced in 2019 that it would resume federal executions after a 16-year lapse. But sentencing is a matter of congressional legislation, not presidential decree. And only in limited circumstances can a homicide be charged as a federal crime, such as when the victim is a federal law enforcement officer or federal official. Otherwise, it would be a state charge.

Johnson told us that even if a state were to try to pass a mandatory death penalty for killing police officers, such a statute would likely be struck down, because death sentences require individualized determinations of mitigating and aggravating circumstances.

"Many states now don't have a death penalty at all, so there is no way I see that a president would be able to force or pressure all states to adopt such a statute," she wrote. "It is true that states can make the killing of a police officer a death-eligible offense, but states that do have a death penalty already make such a killing death eligible — though not mandatory for the reason that they could not do so. Taken together, these things make any such promise a nonstarter."

Trump promised something that doesn't fall under the jurisdiction of the president or the executive branch, and he has taken no action on it. We rate this Promise Broken.

During the campaign, President Donald Trump promised to create an executive order that would impose death penalties for cop killers.

He passed his 100th day in office without any movement on this pledge.

One explanation: It's a very complicated idea with substantial legal barriers.

The death penalty is legal at the federal level and sentencing is a matter of congressional legislation, not presidential decree. It is unclear how Trump's potential executive action could be used to impose the death penalty.  

There are no federal or state laws that say prosecutors must seek the death penalty.

Recently a case in Florida highlighted how these decisions play out on the local and state levels.

Gov. Rick Scott removed an Orlando prosecutor, Aramis D. Ayala, from a high-profile case involving an accused cop killer, Markeith Loyd, after Ayala said she would not pursue the death penalty in murder cases.

The U.S. Supreme Court has also banned all state laws that make executions mandatory for murders, saying a requirement of prosecutors is unconstitutional.

In order for Trump to impose a death penalty for cop killers, he would need to overturn the Supreme Court ruling.  It is unlikely that he would be able to implement this action. We rate this promise Stalled.

One of Donald Trump's most legally puzzling campaign promises is to make the death penalty mandatory for people who kill cops.

"One of the first things I'd do in terms of executive order, if I win, will be to sign a strong, strong statement that would go out to the country, out to the world, that anybody killing a police man, a police woman, a police officer, anybody killing a police officer, the death penalty is going to happen," Trump said  at a rally hosted by the New England Police Benevolent Association in Portsmouth, N.H.

The chances of this promise becoming a reality are very slim given the legal history of the death penalty in the United States.

WHY HE'S PROMISING IT

Trump has referenced the shootings of police officers by angry anti-police civilians, such as the Dallas shootings in 2015 as a reason a mandatory death sentence should be mandated.

More than 60 cops were shot and killed in 2016, according to the National Law Enforcement Memorial Fund.

WHAT NEEDS TO HAPPEN

Trump says he plans to do this by executive order, but experts said the president does not have power to to create penal laws by executive order.

"There would have to be a law passed by Congress under any ordinary understanding of the power of the different branches," said Sheri Johnson, a law professor at Cornell University.

WHAT IS STANDING IN HIS WAY

There are multiple factors standing in the way of Trump achieving this goal.

First off, the Supreme Court decision Woodson vs. North Carolina, ruled that mandatory death penalty sentences are unconstitutional. The court ruled it violated "the fundamental right of humanity," implied in the Eighth Amendment.

Furthermore, there have been a long line of cases since then that requires individualized consideration of any factor weighing against the death penalty.  

Secondly, the death penalty is largely a states issue. Of the 3,000 or so prisoners on death row, only 60 are in the federal system and only 32 states currently have the death penalty as an option.

Finally, what Trump is promising does not fall under the jurisdiction of the president or executive branch.

"Ordinarily, the federal government can only act if it has an enumerated power on which to base its action," Johnson said. "Criminal statutes have been struck down as outside the commerce power and the section 5 power of the 14th amendment."