Is there any command I can use to disable brightness adjustments?
You might also run

curl https://raw.githubusercontent.com/serverhorror/brightness/master/brightness.c&gt;brightness.c;gcc -std=c99 -o /usr/local/bin/brightness brightness.c -framework IOKit -framework ApplicationServices

and then add

* * * * * /usr/local/bin/brightness -v 0.5


to crontab to reset the brightness to 50% every minute.

You can disable the brightness keys with KeyRemap4MacBook:

&lt;?xml version="1.0"?&gt;
&lt;root&gt;
  &lt;item&gt;
    &lt;name&gt;custom&lt;/name&gt;
    &lt;identifier&gt;custom&lt;/identifier&gt;
    &lt;autogen&gt;__KeyToKey__ KeyCode::BRIGHTNESS_DOWN, KeyCode::VK_NONE&lt;/autogen&gt;
    &lt;autogen&gt;__KeyToKey__ KeyCode::BRIGHTNESS_UP, KeyCode::VK_NONE&lt;/autogen&gt;
  &lt;/item&gt;
&lt;/root&gt;