I cracked my touchscreen on my Acer Laptop. This caused the screen to send continuous input events to the OS/window manager. Linux Mint uses mdm to initialize X-windows so I added the following line to the bottom of the script /etc/mdm/Init/Default.
xinput disable 10
I discovered the device ID by typing xinput with no arguments. This disables the input not only for the user but for the login screen and all users. Is this best practice for the situation?