Andy Dick -- He Steals, He Has Drugs ... AND HE DOESN'T GET CHARGED!

Andy Dick was caught with drugs when he was busted earlier this month for grand theft ... but TMZ has learned he won't be charged with either crime.

As we first reported ... Dick was arrested after a guy claimed Dick ran off with his $1K gold chain ... when the two stopped to chat on Hollywood Blvd.

According to the D.A.'s office ... when Dick was popped by cops, he was carrying a single Adderall pill -- and he didn't have a prescription -- so he could have been charged with possession.

But we're told ... the D.A.'s office decided against filing the drug charge because Dick had such a minimal amount. They also declined to file grand theft charges because Dick had already given the necklace back ... and there was no evidence he ever planned to keep it.