MIAMI (NewsNation Now) — All of the charges against a suspect in a May shooting that killed three people and wounded 20 others outside of El Mula Banquet Hall in Miami have been dropped.

Warneric Buckner, 20, was charged with 20 counts of attempted murder and three counts of murder. However, he confessed to detectives after he requested an attorney — which is a violation of his constitutional rights.

“Unfortunately, for this detective, it was a rather huge mistake,” said former prosecutor David Weinstein. “Again, because this defendant invoked his right to counsel after he was in custody and did not want to talk without his lawyer present, the detective should have stopped questioning him.”

In a closeout memo, the Miami-Dade State Attorney’s Office said they can’t move forward without the confession.

“Without the statement, the state of Florida concludes that there is insufficient evidence, at this point in time, to prove the case beyond a reasonable doubt,” the statement read.

Prosecutors said the investigation remains open. They could pursue other charges if more evidence is uncovered. 

Miami-Dade Police are not commenting on the detective’s mistake but said they are committed to pursuing justice for the families.