HOUSTON -

A year-long grand jury investigation into former Harris County District Attorney Pat Lykos ended without finding any wrongdoing.

It was the second grand jury investigation of Lykos to come back with no indictments.

In January 2012, grand jurors looking into possible misconduct in connection with flawed evidence collected by police driving while intoxicated testing vans wrapped up their investigation without handing down any indictments. But the grand jurors sent out a letter accusing Lykos of having staffers investigate them for political connections to her rival and eventual successor, Judge Mike Anderson.

The Texas Rangers moved in to collect evidence and asked for a special prosecutor to conduct the investigation.

On Thursday, the grand jury met for the last time. Afterward, special prosecutor Eric Nichols said that the grand jury's work was done and no indictments will be returned.

Lykos contended both investigations were politically motivated.