Only one moment stands out where a suspect I was interrogating denies any affiliation with the murder victim. I call him out on his lie and show him a torn of half of a letter I found in his apartment, the other half of which was found on the murder victim. But then the game just fails the question for some reason.
But yeah, reading faces is tricky, especially the difference between "doubt" and "lie". I don't know if this is just a case of the game being smarter than me or the game simply making up it's own rules as it goes along.
But honestly, most of the failed questioning is my own fault. There's just too much evidence and motives to keep in mind at certain times.
The thing about the game that actually annoys me the most is the Cole Phelps is kind of a cold fish.