L.A. Noire/A Marriage Made in Heaven

The case starts off with a hit and run felony in a cutscene, which means it's in Traffic's jurisdiction. Go down to your car and head over to the crime scene.

Ray's Cafe
Officer Kaplan will break down the crime scene for you when you arrive, and then you can look around for clues before talking to the witnesses.

When you've found everything, go over to Ms. Perry, the young woman in the blue dress and see what you can find out.

Next up, head inside and talk to the bartender to see if he knows anything.

Use the phone in the back of the bar and you'll have someone run the partial license plate model on the Lincoln Continental. With only one match, you find out the car belongs to William Shelton and the operator gives you his address.

Pattison Residence
When you knock on the Pattison's door, his wife will answer and invite you in. She's not too upset that her husband is dead, and Mr. Sabo is at her house. They claim to just be friends and both say Pattison was killed in the hit and run.

After your conversation you can use the phone in the next room to check your messages. You have one from the coroner, who asks to see you immediately at his office.

Shelton Residence
When you pull up to where Shelton lives, you'll see he's coming out of his apartment building with some suitcases and throwing them in his trunk like he's about to leave town. He knows he's in trouble, so he takes off in his car and you'll need to chase after him. You can pull up on the left side of him to have your partner shoot out his tires, or you can try spinning him out by ramming into his rear wheels from the side. If you don't stop him yourself, eventually he'll crash, so you just need to make sure he doesn't lose you. Keep an eye on the red car icon on the minimap if you lose a visual on him. When you apprehend him, he'll tell you there was no way he could have avoided hitting Pattison and there was a man and woman standing right next to the victim.

Central Morgue
The coroner will tell you that Pattison died from being stabbed with a long, sharp knife, so head back to the wife's house to nab her.

Pattison Residence
This time, things don't go as well as the Pattison house. Mrs. Pattison realizes she's cooked with the abundance of evidence you have, so she admits her husband was murdered, but blames it on Sabo. Sabo doesn't like being pinned with the crime, however, and pulls his pistol. When he shoots Mrs. Pattison, it will start a chase and you'll have to follow after Sabo. You can end this one early with a warning shot also, if you don't want to chase him down to the end.