SAN FRANCISCO (KCBS)— After months of legal wrangling, a San Francisco Grand Jury has formally indicted a former firefighter on three felony drunk driving charges stemming from an incident last summer.

Michael Quinn was reportedly behind the wheel of a fire engine, on a fire call, when he allegedly ran a red light at 5th and Howard Streets and struck and injured a passing motorcyclist.

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Investigators say Quinn left the scene of the crash. He was spotted several hours later at a nearby bar, guzzling multiple glasses of water. When he finally arrived back at his fire station, sources have said that his blood alcohol level was measured at 0.13 percent.

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The District Attorneys office was reluctant to file charges in the case because it was going to be hard to prove that Quinn was drunk at the time of the crash. He ended up resigning from the department a little while later.

Quinn turned himself in to authorities on Monday and posted the $100,000 in bail.

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His attorney, Jim Bustamante, told KCBS that he would likely have more to say about the indictment as soon as it is read. Quinn is due to be arraigned on the charges this Wednesday.