Emptying the history

is there any other way for someone to see the history of my commands after i've nulled the .bash_history file?

i'm curious. i usually do this each time i want to prevent spies:

cat /dev/null > .bash_history

i work in an environment where multiple people have root access. meaning, we can all "sudo -sE or sudo su - root".

OS:linux/sunos/hpux

They could back up your history file every time you login and logout, install rootkits, or any number of things. You cannot prevent root from being root.