Janna Herron

USA TODAY

Serena Williams is using her celebrity to spotlight a common but little understood form of domestic violence: financial abuse.

The tennis superstar and woman’s advocate stars in a new public-service video called “Invisible Weapon” from the Allstate Foundation Purple Purse campaign that contrasts the visible signs of physical abuse with the hidden ones of financial abuse.

Financial abuse is when the abuser controls access to money, including hiding assets, keeping a victim to get a job or denying them access to a bank or credit card account.

The video also highlights the prevalence of this abuse; 99 percent of domestic violence victims also suffer some sort of financial abuse. Purple Purse offered USA TODAY an exclusive look at the video.

Serena’s involvement

Williams, who spoke to USA TODAY about her role, said she knew people in her life who had been victims of domestic abuse. Still, the 99-percent figure of financial abuse struck her.

“That is an incredibly high number,” Williams noted. “So, I’m thinking of people I knew in the past, that were probably experiencing this too," she said, adding "so that’s even more reason to lift my voice,” for this cause.

This is Williams’ second year acting as an ambassador for Purple Purse. Last year, she designed a limited-edition handbag for the foundation’s Purple Purse Challenge, an annual fundraising competition in October. This year, she created a purple backpack.

Williams is also working on the foundation’s anti-domestic violence mural project that kicked off this summer and goes through the end of October. The goal is to get people talking about domestic violence on social media.

“The foundation helps women find a way out of abuse through financial education,” Williams said. “This is something that affects so many women and so many people and it’s important to raise more awareness.”

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What is financial abuse?

Hard to spot, financial abuse is “a control tactic that keeps victims trapped in abusive relationships,” said Vicky Dinges, head of Purple Purse Vicky Dinges and Allstate's senior vice president of corporate relations.

For instance, one survivor Dinges knows had a husband who wouldn’t let her hold a job and controlled the household spending, including limiting how much she could use for groceries. During one trip to a store, a cashier asked the woman if she wanted to “round up” her grocery purchase to get cash back.

“A light bulb went off and she began getting $5 or $10 each week, hiding the cash in a box of tampons, which she reasoned her husband would never find,” Dinges said. After two years, the woman saved enough to hire an attorney and file for divorce.

Signs of financial abuse

Part of the problem is the lack of awareness. Nearly 50 percent of respondents in a Purple Purse survey this year didn’t know that financial abuse is a form of domestic violence. But more than four out of five believe that not having enough money would make it very or extremely difficult to leave an abusive relationship.

While financial abuse almost always accompanies another form of abuse – physical, sexual or emotional – it can also exist on its own. Here are red flags that a loved one may be in a financially abusive relationship.

They are not allowed to get a job.

They can’t access money on their own.

They aren’t allowed to have credit cards.

Their spending is tightly monitored or restricted by their partner.

They are overly worried about how their partner will react to everyday purchases.

If you or a loved one is in an abusive relationship, you can call the National Domestic Violence Hotline at 1-800-799-7233 or TTY 1-800-787-3224 for help. If you want to help survivors of domestic violence, you can donate to nonprofits through PurplePurse.com.