It is a new policy in fact.
The washington post did a article on this.
"Obama’s guidelines prioritized the deportation of gang members, those who posed a national security risk and those who had committed felonies. Trump’s January 2017 executive order does not include a priority list for deportations and refers only to “criminal offenses,” which is broad enough to encompass serious felonies as well as misdemeanors."
From the article I linked above
Interestingly, Trump has released a hundred thousand people caught even though he said he'd stop the "catch and release" policies.
Evidence?
Looked up wherever more illegals = more crime.
"
Some
academic researchers have examined quasi-natural policy shifts to see how crime rates change due to more intense immigration enforcement. If illegal immigrants are more crime-prone, then more aggressive immigration enforcement in an area should lower crime rates. But they found no overall reduction. This suggests, at a minimum, that illegal immigrants' crime rate is no higher than that of the broader population.
More
recent research conduced by Michelangelo Landgrave and me finds similar results. We applied a statistical technique that is used to figure out the employment, age, and occupations of immigrants in the census to the incarcerated population data in the American Community Survey. This allowed us to estimate the percentage of illegals among the incarcerated. We found that even if one includes in the mix those in detention facilities—most whom are there for immigration-related offenses—illegal immigrants are 44 percent less likely to be incarcerated than native-born Americans. Excluding those in immigration detention yields an incarceration rate that is almost identical to that of legal immigrants: A dramatic 69 percent lower than that of natives.
"
Source on illegals voting?
