Cannot filter model by state

Hello and thank you for this great compo.

I have created a basic component with 1 table. This table contains the default "state" field.

Then , in the frontend, I am loading my Model and apply filters in order to select certain rows from the table.

For example:
$model->setState('filter.receiver',954); //This filter is for the receiver field. So, only rows with receiver value of 954 are returned.

However, the following does not work.
$model->setState('filter.state',1);

In other word I need to return only the items that are Published (state=1).

Is this the default behavior or a bug.

I appreciate your help and I hope my issue is clear.

Thanks

Haris