blur the lines

[Wookie]

Detective: What'd you do with the diamond rattlesnakes?
Suspect: What do you care? Are you going to arrest me for blurring the lines?"
Detective: We're leaning towards murder.


Does "blur the lines" mean "not cooperate in criminal inverstigation"?
I couldn't even google it.

What does that idiom mean?
Also I want to know why the plural form "lines" instead of "line" is used here.

[Naamplao]

Detective: What'd you do with the diamond rattlesnakes?
Suspect: What do you care? Are you going to arrest me for blurring the lines?"
Detective: We're leaning towards murder.


Does "blur the lines" mean "not cooperate in criminal inverstigation"?
I couldn't even google it.

What does that idiom mean?
Also I want to know why the plural form "lines" instead of "line" is used here.

One would hope that, in the battle between good and evil, there would be a clear distinction between the two, but everything is not so black and white.

A "blurring of the lines" means that the distinction between one side or the other is not clear all the time. In other words using my example, sometimes the good are less than good and the evil do good things once in a while. So at times it is difficult to tell one from the other.