My mistake - and my apologies - you were right.
The Levitique (sorry for the French name but I'm not an expert on biblical translation !) do not say the man who's slept with a woman during the time she's impure will be put to death. Such a man will be "expelled" (once again, the translation may not be very accurate here)from the Lord's people, as would be the man who sees an "impure" woman naked.
Thank you. A lot of people mis-read Biblical passages either inadvertantly or on purpose. In Exodus, there are several passages where God instructs the children of Israel to kill all the inhabitants of the land, and their flocks. That is a very specific instruction and was only given to them and is not to be construed as something we should do today.
It's important not only to know what the Bible says, but also to know to whom it was said.