Victim white,thief mexican immigrant,cop mexican. Is this outright discrimination?

Okay so here's the situation. My mother went to pick up a pizza and accidentally leaves her cell phone on the counter. She realizes after she gets home. We call the phone and are greeted by a spanish word. After a few minutes,spanish speaker puts English speaker on phone. English speaker lets me know that they took the phone from the pizza place. I say you have 15 minutes to return the phone or I will call Mesa police. Phone isn't returned. A mexican policeman comes to my door and informs me the people who took the phone had called the department after I threatened them wanting to turn over the phone. I say, I want to press charges and the mex cop says,they didn't break the law since my ma left the phone at the pizza place. I say stealing is against the law isn't it and who's going to pay for the calls to mexico(yes,there are 4 of them on the account,I was informed by tmobile). He says nothing he can do and leaves. No report,nothing and we're left with the bill. Discrimination or no?