Mark Humphrey/Associated Press

San Francisco 49ers cornerback Chris Culliver pleaded not guilty to charges stemming from an alleged hit-and-run incident in March, but the fourth-year pro may have to pay dearly for his actions.

According to Lisa Fernandez of NBCBayArea.com, Culliver is facing a civil lawsuit after allegedly threatening a 15-year-old with brass knuckles.

The alleged incident occurred on March 28 after Culliver hit a cyclist as well as an SUV in San Jose, California. Mark Santos, who was the driver of the SUV, reportedly followed Culliver and blocked him as he waited for police to arrive on the scene.

Santos alleges that Culliver yelled obscenities and slurs at him and his family. He also alleges that Culliver brandished brass knuckles and threatened to hit his 15-year-old son.

In the claim filed by Santos, Culliver was admonished for his alleged actions.

"We live in a civilized society ... governed by rules that demand the respect for the inherent dignity of mankind," the claim states. "Thus, we do not strike a man down and leave him for dead. Nor do we brandish brass knuckles upon 15-year-old children."

This is far from the 49ers' only offseason issue. According to Eric Branch of the San Francisco Chronicle, three members of the Niners' 2011 draft class have been investigated for something over the past few months:

Culliver's situation is particularly difficult since he could potentially be punished in a number of different ways. Not only is Culliver still facing criminal charges, but he could also lose a substantial sum of money in the civil suit and get suspended from the NFL as well.

That would pose a huge problem for a 49ers team that is already light at the cornerback position after Tarrell Brown and Carlos Rogers both signed with the Oakland Raiders this offseason.

San Francisco opted to select Northern Illinois safety Jimmie Ward in the first round of the 2014 NFL draft, but there is still a major hole at corner with or without Culliver.

Regardless of the circumstances surrounding this case, Culliver's reputation has already taken a major hit in the court of public opinion. The charges are so significant that the Niners could potentially go to great lengths to remove themselves from the situation.

Releasing Culliver would hurt San Francisco's cornerback depth even more; however, the 49ers need to do something to combat the negative publicity they have received as of late.

Perhaps Culliver will be the sacrificial lamb in that regard.

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