Which is most important to check when inspecting by touch a possible fraudulent piece of id?

The most important thing to check in this case is the thickness of the identification card. Identification cards usually have standard thickness. Ask for the ID card and run your thumb over it, checking its thickens, whether it is uniform with the normal ID card. In a situation where a picture is pasted over the original one, the thickness will be more in that area. 

Can you include the paragraph too ?

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