Three whodunits: part 3 of 3

here's mystery #3:

Old Mr. Teddy is found dead in his study by Mr. Fiend, who recounts his discovery to the police:
"I was walking by Mr. Teddy's house when I thought I would just pop in for a visit," Mr. Fiend says. "I noticed his study light was on, and I decided to peek in from the outside to see if he was in there. There was frost on the window, so I had to wipe it away to see inside. That is when I saw his body. So I kicked in the front door to confirm my suspicions of foul play. I called the police immediately afterward."
The officer immediately arrests Mr. Fiend for the murder. How did he know he was lying?

there wasn't a frost that morning

plus, his name was FIEND!!!!

and, no one looks in the house of the window before ringing the door bell to see if they are even home in the first place,


or, there was no light on in the study,

or, skullkings idea.

any other thoughts?

nope

apparently, frost forms on the inside of the window, not the outside. so Mr. Fiend couldn't have wiped away the frost from the outside.

again I was on the right track

i just dont get why frost cant form on the outside of the window.

percipitation?! or somthing like that.

since its warmer inside, the water forms there, and since the window is cold it freezes?

IDK