Sentenced to life in prison in November for armed robbery, LaDondrell Montgomery insisted he was not the shadowy figure on surveillance video. He swore the eyewitness identifying him were flat wrong.

If only the 36-year-old habitual offender had an alibi. If only he could remember exactly where he was that day of the robbery.

A week after jurors sentenced Montgomery, his attorney was researching the felon's lengthy rap sheet.

In that file was a report that had details about a 2009 arrest and an iron-clad alibi: He was in jail.

Released from custody about nine hours after the December 13, 2009 crime, Montgomery was actually innocent.

"We didn't know," said attorney Ronald Ray after the conviction was thrown out Thursday. "We didn't learn that until several days after the trial."

Ray said Montgomery was in and out of custody so many times he did not remember exact dates. The defendant even testified in his trial and never brought up the startling fact.

"He couldn't remember. We asked him where he was on all the cases he's been charged with," Ray said. "He just couldn't remember, for that particular date, where he was."

Both sides scolded

Ray said he did not know about the misdemeanor domestic violence Montgomery was charged with in 2009, although he had access to the public files.

State District Judge Mark Kent Ellis shook his head as he berated Ray and prosecutors for the oversight.

"It boggles the mind that neither side knew about this during trial," Ellis said Thursday. "Both sides in this case were spectacularly incompetent."

The judge personally apologized to Montgomery, who stood at the bench in an orange jail uniform.

Ray said he has been working to untangle his client from six alleged robberies.

"I have freed a man from a life sentence, so if you want to say I'm incompetent for doing that, I'll accept that with a smile," Ray said.

Remains in custody

Now facing just five other counts of robbery, Montgomery remains in custody. He has been convicted of several robberies and assaults since 1998.

Assistant Harris County District Attorney Alison Baimbridge said the first time she or anyone in her office was told about the alibi, in a motion for a new trial, the office investigated the claim.

Once satisfied the Harris County jail record was accurate, Baimbridge joined the request for a new trial, nullifying the conviction.

Baimbridge then dismissed the charge.

"It's happened before," Baimbridge said after the hearing. "Normally, we are notified prior to or during trial, that the defendant may have been in custody during the time of the offense - and we investigate it."

She pointed out that prosecutors generally cannot question suspects.

"I have not ever personally spoken with this defendant," Baimbridge said. "That information, everyone would assume, would come from the person in custody."

'Free my husband'

Montgomery's mother and wife attended Thursday's hearing and said afterward they believe he is innocent of all the charges.

"Free my husband," Shanthina Guillory Montgomery said as she bounced the couple's 2-year-old daughter on her hip. "He's an innocent man."

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