Is the border open?
Not quite. The Biden administration is leaning on a public health law invoked by the Trump administration to quickly expel migrants who are encountered at the US-Mexico border, typically single adults and some families.
In February, for example, the majority of migrants encountered at the US-Mexico border were immediately turned back -- and some of those tried to cross again. Numbers had started to steadily climb last summer.
Of the nearly 97,000 migrants who crossed the border illegally in February, around 70,100 were turned away, according to US Customs and Border Protection data
. Those numbers may reflect some repeat crossers. If not for that Trump-era policy, they would generally be processed and come into US custody.
That is similar to how the border was operating over the last year under Trump, except for one difference -- unaccompanied migrant children aren't being expelled.
The Biden administration, in the case of children, reverted to the process as it was pre-pandemic -- accepting unaccompanied children into the US and transferring them to the custody of the Department of Health and Human Services, which is charged with their care.
"With kids we're seeing something unique that is larger than what we've seen before," said Andrew Selee, president of the Migration Policy Institute, a nonpartisan think tank. "With adults we're also seeing larger numbers than we have in recent years, but they're not getting in."
When was the last border crisis and how bad was it?
In 2019, the Trump administration faced high numbers of families and children coming to the US southern border. During the 2019 fiscal year, the Border Patrol arrested more than 473,000 migrant families and around 76,000 unaccompanied migrant children.
The flow of migrants overwhelmed government resources, resulting in overcrowding at Border Patrol facilities and in some cases, children seen sleeping on the floor.
May 2019 saw the highest number of overall apprehensions: 144,000.
How does 2019 compare with 2021 for children?
As far as unaccompanied minors, the number of children arrested at the border in March will likely easily surpass the high during May 2019, when around 11,400 unaccompanied children were arrested, according to preliminary government data CNN has reviewed
The trend is unmistakable. In February, more than 9,200 unaccompanied children were arrested by US Border Patrol on the US-Mexico border, up from 5,694 in January, according to the latest available CBP statistics.
In May 2019, at the height of that crisis, 11,475 unaccompanied kids were arrested by US Border Patrol. In February of that year, 6,817 unaccompanied children had been arrested.
We're still early in the year, which is why the accelerated pace of arrests is so concerning. Seasonal trends tell us numbers go up in the spring and summer.