As part of the standard procedure, those arrested will be have their criminal histories checked as police search for any outstanding warrants, said Park Police spokesman Lt. Richard Butler said.
“The only time immigration ever comes up is if there has been a hit or a flag that has come up from other departments,” Lt. Butler said.
It was unknown whether any of the 145 people arrested were illegal immigrants and would have been at any risk of deportation.
A spokeswoman for Casa de Maryland, which organized the rally, said the organization offered a legal intake service to rally participants ahead of the demonstration to advise protesters of their legal status so they would be aware of the potential risks of getting involved in the protest.
“We have a group who is undocumented and they really wanted to do it,” said Casa spokeswoman Susana Flores, who estimated that up to 1,000 demonstrators attended the protest.
The protest began Thursday morning outside of Immigration and Customs Enforcement headquarters and before demonstrators marched to the White House to demand that action be taken on immigration reform.
As of late Thursday afternoon, some of the arrested protesters had been released from the Park Police booking facility after paying the $50 fines for the offense.