How to test a catylictic converter without it being connected to a car?

Last year I bought an 02 Honda Civic LX and this year it needs to be smogged. When I bought the car as is, the owner gave me the Catylictic converter along with the car. The thing is that he told me the cat converter still works, however is there a way to test it before I have a professional install it that way I'm not wasting time and money buying a brand new one and having that installed?

Currently it doesn't have a cat and I know that it is illegal. Who exactly enforces that? If I take it to a certified smog place and have them install the cat converter and they find that my car didn't have one since I bought it, do they have to report that to the DMV? The last thing I want is to pay an outrageous fine for not driving it with a cat converter? I don't know if it varies with state rules or anything, I live in CA.

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