See Law & Order: Justice Is Served Hint here!

The password of victim's locker is ACE.
The password of locker of victim's mother is 1614

Piano Code
The code to the piano lock box in the victims apartment: C, #, C, #, C, #, B, C,
#, D , E , D, C, #.

Typewriter Puzzle
At the end of the investigation, you need to choose the right letters on the
keyboard sent from the crime lad. There are 12 letters each stacked 3 high.

First line ... second H, third Y, third Q, first A, first S, third J.
Second line first F, second R, first E, second T, second C, third O.