The Liberty’s play on the court has been strong this season, but the players’ commitment to social activism is perhaps even stronger — and a bit costly.

The WNBA has fined the Liberty, Phoenix Mercury and Indiana Fever and their players for wearing black warm-up shirts in the wake of recent shootings by and against police officers. All three teams were fined $5,000, and each player was fined $500.

On Sunday afternoon, members of the Liberty donned warm-up shirts memorializing and mourning the victims of last week’s police shootings, featuring the hashtags #BlackLivesMatter and #Dallas5.

Speaking with their teammates behind them after their 82-70 loss to the Fever Thursday at Madison Square Garden, the Liberty’s Tanisha Wright, Swin Cash and Tina Charles said the players will continue to advocate for the African-American community.

“We really feel like there is still an issue here in America and we want to be able to use our platforms.’’ Wright said. “We don’t want to let anybody silence us in what we want to talk about. It’s unfortunate that the WNBA has fined us and not supported its players.

“We feel like America has a problem with the police brutality that’s going on with black lives around here.”

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Cash also said “we really would appreciate that people stop making our support of ‘Black Lives Matter’ — an issue that is so critical in our society — as us not supporting police officers. It’s not mutually exclusive. You can support both things, but at the same time, this issue is important to us.”

Wright said: “People put this imaginary black lives ‘only’ matter whenever people say black lives matter. What we’re saying is black lives matter, too. Period.”

Charles was concerned by the shooting of behavioral therapist Charles Kinsey on Monday in Miami. Kinsey reportedly was still hospitalized yesterday with a leg wound. He “was down and just trying to help an autistic person out,’’ she said. “When I heard about the news, I just couldn’t be silent.”

Wright noted that WNBA teams have supported other social issues.

“The majority of this league is made up of black women, so this is something that directly affects us,” she said. “We need to be just as supportive with this issue. Breast cancer awareness, they support that. Pride, they support. ‘Go green’ initiatives, they support. We want them to hear our voices and stand with us and support this as well.”

In issuing the fines, the WNBA said the league’s uniform code states “uniforms may not be altered in any way.”

“We are proud of WNBA players’ engagement and passionate advocacy for nonviolent solutions to difficult social issues but expect them to comply with the league’s uniform guidelines,” WNBA president Lisa Borders said in a statement.

Liberty players wore their traditional warm-up shirts with the team’s logo Thursday, but Charles wore hers inside out during the shootaround and a pregame ceremony in which she received the WNBA player of the month award for June.

Liberty loses to Fever. Lynetta Kizer had 21 points for Indiana (12-12). Charles scored 25 for the Liberty (18-8), which enters the Olympic break leading the Eastern Conference. It will resume play Aug. 26.

With AP