Why do immigration officials continue to practice capture and liberation? Why thousands of illegals are released in the country? Because we are?

The district attorney has the right to decide whether to prosecute people arrested by the police. Also, the judges of the criminal courts are very political. The people released are probably considered harmless, they can have families to support, they can have asylum requests because of the violence in their country, they can be important for influential people in the community because they work for them, etc. Trump honestly opposes additional immigration that is illegal; But those who are already here often remain outside the convenience of officials, judges, politicians and community leaders.