Blue Bloods Season 11 Episode 4 revolves around tough decisions.

Erin successfully prosecutes a drunk driver who killed a little girl. The girl's mother, Diane, wants her to recommend the strictest possible sentence. Erin agrees... until Farmer risks his life to save some children on a playground from a knife-wielding assailant. Erin wonders whether Farmer's good deed should be taken into account when making the sentencing recommendation despite the gravity of his crime.

Meanwhile, Frank must deal with a detective who is now in a wheelchair due to being injured in the line of duty. She still wants to work in the field and refuses to take a desk job, making it clear she is going to remain an investigator. She continues to work off the books despite Frank's insistence that it's too dangerous.

Elsewhere, when one of Jamie's cops is shot, the cop's partner blames himself. When the perp turns up dead, Flores is accused of the crime and won't defend himself. Jamie and Eddie are left to investigate what happened on their own.

And finally, Danny is sure he has the right man while investigating a ride-share rapist, but proving it is another story.

To find out what happens, watch Blue Bloods Season 11 Episode 4 online.