Pass object to velocity template

I’ve created an custom searcher:

import com.atlassian.jira.issue.customfields.searchers.MultiSelectSearcher;
import com.atlassian.jira.util.JiraComponentFactory;
import com.atlassian.jira.util.JiraComponentLocator;

public class SingleSelectFieldSearcher extends MultiSelectSearcher {

public SingleSelectFieldSearcher() {
super(new JiraComponentLocator(),JiraComponentFactory.getInstance());
}
}

I’ve assigned this searcher to my custom field type. The velocity template for this custom searcher is a copy of the default.

Depending on the project role of the current user I want to hide the options when searching for issues. Therefore I’ve a class providing a getter() for this (allowed/not allowed).
Question: How can I access my object inside the velocity template to skip the output of the options?

Thanks