Object in inline onclick event

Why is this not working ?

<img id="xx" src="/Content/components/imgs/add.gif" onclick='ShowLookup({"id": "22","name": "Robert Pitt"})' />

or

<img id="xx" src="/Content/components/imgs/add.gif" onclick='ShowLookup("id": "22","name": "Robert Pitt")' />

When I click on the image I got an error: Invalid property id

Works like a charm for me :

http://jsfiddle.net/neebz/uwywG/1/