Murder in the confined

Miss Ashley was found dead in a confined room in her apartment parking lot, today, prior to dawn. The cops started the investigation about 10 hours ago at 6 AM. They discovered no clues or information regarding the way she was killed. 

I just got a call about this, a CID officer appealed to me to investigate the case. I went there, elegantly riding my bullet motorbike under the brightly shining sun on a smooth, narrow road between the shimmering dry grass.

There were easily twenty officers including the senior officer who called me with the permission of the commissioner. The apartment didn't have a tight security team. It had around four blocks and the height couldn't be anything more than twelve floors.

I entered the crime scene, a confined room in the ground floor parking lot.

A tall woman was on the floor, untouched for hours, a few old good-for-nothing worn-out stretchers at the side of the square room. No stabs, no marks of blood and bullets weren't sighted in the room. The room didn't have windows to be conspicuous and wasn't in any camera's sight. I've never investigated a case like this one.

I ceased thinking and scanned the room. I found something; a shirt button. I could barely smell perfume.

When I left the room, the entire squad was squinting at me. I wanted to do this case behind closed doors. I lifted my arm to show the button and said, "This is what I found officers". They looked gloomier when I announced this. Not even one of them was interested in taking the only clue.

I was at the commissioner's office within ten minutes and now I'm permitted to check the city CCTV cameras. I got the number plate of a guy's bike who was riding near the apartment with three of his buttons undone. I took his address and headed there.

When he opened the door, I recognized him and said, "May I please enter, need to investigate." in a humble tone.

He replied "Show me your ID card, then I'll let you in.", in an ignorant careless manner.

I googled and showed him the picture of the commissioner.

"Why're you showing this to me now? Show your ID card."

I started a video call with the commissioner and said, "Sir, I need to check this flat once, can I continue?."

"Sure"

"Please tell the same to him, the owner of this flat."

"Please let him do the investigation, thank you."

The guy trembled and moved back, making a path for me, to enter.

It was six o'clock, and the beginning of summer. This guy turned all the lights off and had a gloomy room with sunlight entering from translucent windows.

I strode straight to the bedroom. A perfume bottle and another bottle of pepper spray were relaxing on the dressing table below the mirror. I sprayed the perfume on him, it was strong and the smell wasn't unlike the one in the confined room.

His wardrobe didn't have any shirt with a lost button. Am I wrong? It's supposed to be this guy.

I ran into his laundry room and took the only shirt from the basket above the washing machine. I got hold of the only clue in the case. It was exactly like those on the shirt, and of course, the shirt had lost the third button from the top.

I texted the CID officer, "First suspect found" and shared the location. The suspect was shifted to the investigation room. 

The officer started the investigation, "Why did you murder Miss Ashley?"

He leaned onto the table and told, "No comments . . ."

"So you're the one who murdered Miss Ashley?"

"Yeah"

"At least tell us why you murdered her"

He refused again.

I still had one question.

I asked the senior CID officer, "Sir I really wanna know something, can I ask him."

The officer agreed before I entered the room and took the closest seat to the killer.

"Can you just answer one question"

He looked up, and back down after a second.

"How did you murder her? Bullets, weapons or wounds weren't sighted."

He grabbed a paper out of his back pocket and left it on the table.

He looked at the investigator, "No more questions shall be asked and no more answers will be given."

The final judgement said that he'll be imprisoned for five years.

The paper that he left on the table was a medical shop bill with only one product bought;

"Sleeping pills"