When Cristopher was charged with attacking his ex, a well-timed selfie told the real story.

A Texas man facing 99 years in prison has a selfie to thank for his freedom.

September 22, 2017 started just as any other day for 21-year-old Cristopher Precopia: He woke up and went to work at a lumber yard as usual, but as time went on his day started to spiral.

During the day, police turned up and arrested him, but he wasn’t sure why.

Following the arrest, he discovered he was facing a felony charge of burglary of a habitation with the intent to commit other crimes, with a maximum sentence of 99 years.

Cristopher’s high school ex-girlfriend had accused him of breaking into his ex-girlfriend’s home, attacking her and carving an ‘X’ into her chest with a box cutter.

The two dated for about six weeks while Cristopher was a 17-year-old high school senior and she was a 15-year-old sophomore, his mother Erin Precopia told ABC News.

According to his attorney, Cristopher had not had contact with his ex for more than two years.

She claimed the attack happened on September 20, two days before his arrest, but Cristopher knew he hadn’t committed the crime. He couldn’t have.

“I had no idea why everything was happening, and I was lost,” he told Texas news station KVUE.

He was taken to Williamson County Jail, where his parents posted a $150,000 bond.

Then they began the fight to prove his innocence.

On the night of the alleged attack, Cristopher was out of town. He was with his mother Erin at a hotel about 105 kilometres from the accusers home.

Erin had posted a group selfie around the same time the alleged attack occurred – Cristopher can be seen smiling in the left corner.

The photo was on Facebook. Timestamped and geo-located.

There were also sworn affidavits from several people who were with him that evening. He had a watertight alibi.

According to KVUE, police experts said in most cases investigators should attempt to interview a suspect before filing charges to determine if they have an alibi.

"You may not get any more information than you had, but it gives you an opportunity for the suspect to react, respond, deny," Bruce Mills, a former Austin assistant police chief and policing consultant told KVUE.

"Certainly a case where the suspect appeared to be available, it would be more step you could take."

In Cristopher's case, police reports show he returned a phone call and left a message with police before he was arrested.

Nine months after the arrest, the Bell County Prosecutor's Office dismissed the cause "in the interest of justice", according to ABC News.

His accuser told police she and Cristopher had a troubled relationship during high school and cited that as her reason she reported that he assaulted her.

Though he is now cleared, Cristopher was still left to face repercussions from the false accusation.

His parents paid the 10 percent in cash of his $150,000 bail and racked up another $100,000 in attorney fees, attorney Rick Flores . For nine months, Cristopher had to check in with a bail bondsman once a week, his mother said.

Over 12 months later, Cristopher told KVUE he is ready to move forward.

"I'm ready to actually live my life, the way I want to, without having any kind of worry that this can come back and hurt me," he said.