The lawsuit, seeking at least $1 million in damages, said Martinez "sustained substantial injuries, including, but not limited to past and future mental anguish, injuries to his name and reputation in the community, expenses incurred for his criminal defense, posting of bond and for expungement, lost wages and loss of earning capacity."

According to the complaint, the credit union, Fox and Archer:

• Failed to provide truthful and accurate information during an active police investigation.

• Failed to ensure that information published about Martinez was truthful and accurate.

• Offered false opinions to the police regarding Martinez's guilt or innocence.

• Failed to adopt policies, procedures, customs and practices – such as training staff on how to properly conduct investigative activities – that would have prevented the incident.

The credit union and Fort Worth attorney Mark Haney, who represents Martinez, declined to comment.

According to court documents, on around Oct. 6, 2013, fellow Forth Worth police employee and FWCCU member James Tate told the credit union he had discovered an unauthorized withdrawal from his savings account had occurred on Sept. 6.

Tate went to a FWCCU branch, where he was shown a drive-through video allegedly filmed at or about the time of the unauthorized withdrawal, the court documents said.

The video showed a Fort Worth City Marshal's vehicle at the drive-through window but the video quality was not adequate to identify the driver, the complaint said.

Although the time on the video tape was inconsistent with day when $500 was taken out of Tate's account, he was allegedly assured by Archer that the transaction involving the police vehicle was associated with the unauthorized withdrawal, the lawsuit said.

Police later pinpointed that Martinez had been the driver and were told by credit union staff that Martinez had not made any transactions on his own accounts on Sept. 6, the court documents said.

Based upon that information, Tate signed an affidavit for fraudulent use or possession of identifying information, a state jail felony offense, and the police launched a criminal investigation, according to court documents.

Martinez cooperated in the interview and repeatedly stated that he did not commit the crime, but he was immediately placed on paid administrative leave, the complaint said.

Martinez was arrested Oct. 15 and released after posting $5,000 bond, the court documents said.

During the investigation, the credit union continued to contend that Martinez had not made any personal banking transactions that day. As the investigation progressed, detectives learned that the teller who handled the $500 transaction recently been fired due to job performance issues, the lawsuit said.

The former employee later confirmed that he had been fired from the FWCCU due to repeated clerical errors, and denied knowing Mike Martinez or conspiring to assist in taking any money from the FWCCU, the court documents said.

During an administrative hearing at the police department on Oct. 22, Martinez produced evidence demonstrating that he had made a deposit of $479.38 into his FWCCU account on Sept. 6 and he identified the source of both checks making up the deposit, the court documents said.

Despite providing evidence he made a transaction, Martinez was immediately terminated and the Fort Worth Star Telegram ran a front page article titled "Fort Worth City Marshal Faces Fraud Charge" with his mug shot, the lawsuit said.

As the investigation continued, Fox allegedly told detectives that he did not think that there was any other explanation for the unauthorized withdrawal other than that Martinez had taken the money, the court documents said.

When asked whether an accident could have been occurred, Fox denied that the account numbers of Martinez and Tate were similar, and he once again confirmed that Martinez had not made any personal FWCCU transactions on the date in question, the lawsuit said.

Investigators then asked Archer if he could search to determine if a transaction was made for a specific dollar amount on a specific date, and Archer stated that he could, the complaint said.

Upon request, Archer said he would conduct a search for $479.38 on Sept. 6 and call the investigator back, but instead a call came from Fox, who said that the previous information was not accurate and that Martinez had made a $479.38 deposit on Sept. 6, according to the lawsuit.