Public static boolean property becomes false in __destruct

I have a class with a static public boolean property which is supposed to be false. It's set to false on initialization ("public static boolean $myvar = false;"), and overridden to false again in __construct. I've also dumped the value of the property in nearly every function in my application, and the value remains false. However, when I actually check the property in a if in the class destructor, it evaluates to true. I've also set a breakpoint with xdebug, which shows the value of the property to be true at this point. I've done a full search, and nowhere in my application should the value become true; the only place where it's modified is "MyClass::$myvar = false;" at one point. Does anyone have any idea why the boolean property's value appears to be true in the __destruct, despite never being set to true? Thank you in advance.