The Trump administration can't get its story straight when it comes to its new "zero tolerance" policy that has separated thousands of migrant families.

Some in the Trump administration have resisted referring to the tactic as a "policy." Others have described it as such and advocated its use as a deterrent.

As critics have pointed out, the differing explanations contradict one another.

As the Trump administration faces heightened scrutiny for its family-separation tactic, various government officials have contradicted one another in explaining what exactly is going on with migrant families at the border — and why.

The administration recently implemented a "zero tolerance" policy in which all adults held on suspicion of immigration violations at the US-Mexico border are priorities for criminal prosecution, an action that separates them from any children they're traveling with.

While some officials have advocated the policy as being necessary to deter illegal immigration, others have shied away from even describing it as a policy.

As critics have pointed out, not all of these explanations add up.

Here's what several officials in the Trump administration have said about the policy:

It's a deterrent

President Donald Trump's chief of staff, John Kelly, at the White House on May 7. Associated Press/Andrew Harnik The White House chief of staff, John Kelly, told NPR last month that separating families at the border would most likely dissuade migrants from attempting the deadly journey to the US and would ensure that asylum cases get processed more quickly.

"It could be a tough deterrent — would be a tough deterrent. A much faster turnaround on asylum-seekers," he said, brushing aside concerns that it could be cruel to separate young children from their parents.

"The children will be taken care of — put into foster care or whatever," he added. "But the big point is they elected to come illegally into the United States, and this is a technique that no one hopes will be used extensively or for very long."

President Donald Trump's senior policy adviser, Stephen Miller, has taken a similar view. He told The New York Times this week that the previous practice of releasing immigrants seeking asylum into the US while their cases were pending acted as an incentive for illegal immigration.

"It was a simple decision by the administration to have a zero-tolerance policy for illegal entry, period," he said. "The message is that no one is exempt from immigration law."

It's in the Bible

The Trump administration has had to contend with growing backlash from a key part of Trump's base — evangelical Christians.

Attorney General Jeff Sessions defended the policy to people he called his "church friends" last week, citing the Bible's guidance to obey the government's laws, though there is no US law requiring the separation of migrant families.

"I would cite you to the Apostle Paul and his clear and wise command in Romans 13 to obey the laws of the government because God has ordained the government for his purposes," Sessions said.

Sarah Huckabee Sanders, the White House press secretary, also cited the Bible when defending the zero-tolerance policy at a press briefing last week.

"I can say that it is very biblical to enforce the law," she said. "That is actually repeated a number of times throughout the Bible."

It's the Democrats' fault

People seen at a facility in McAllen, Texas, on Sunday after being taken into custody on suspicion of illegal entry into the US. Customs and Border Protection's Rio Grande Valley Sector via Associated Press

Trump himself has repeatedly blamed Democrats for the policy, falsely saying on Twitter and in interviews that his administration is merely "following laws" that Democrats created.

"I hate the children being taken away," Trump told reporters last week. "The Democrats gave us the laws. Now, I want the laws to be beautiful, humane, but strong. I don't want bad people coming in."

As numerous critics have pointed out, there is no law requiring family separation. The Trump administration's zero-tolerance policy is just that: a policy.

Though the Trump administration has cited several "loopholes" in immigration law that they wish to close as a means to stop illegal immigration — and therefore remove the need for a zero-tolerance policy — none of the existing laws mandate separating families.

There is no family-separation policy

Homeland Security Secretary Kirstjen Nielsen addressed the news media at the White House on Monday. Associated Press/Pablo Martinez Monsivais

Homeland Security Secretary Kirstjen Nielsen held a combative press briefing at the White House on Monday, stunning reporters when she denied that the Trump administration created a family-separation policy and saying it was "offensive" for reporters to suggest that it had.

"Why would I ever create a policy that purposely does that?" Nielsen said. "This administration did not create a policy of separating families at the border."