Kate Beckett:  It 's one thing for you to look out for your friend . It 's a completely different story when you hide vital information from me .
Richard Castle: I was n't hiding it . I just did n't think it mattered .
Kate Beckett: You did n't think it mattered that Damian was a suspect in a previous homicide ?
Richard Castle: I did n't know he was a suspect . And since he was never arrested , and that case is still unsolved , I 'm guessing those cops have a lot of theories and no evidence , like another detective I could name right about now .
Kate Beckett: You know , if this was anybody else , you 'd be asking me why I had n't already slapped the cuffs on him .
Richard Castle: But it is n't anyone else . And I am telling you , you 're way off base on this _ one _ .