は違法です

is illegal

→ は
phrase Rare #22,335
is illegal A polite expression meaning that something is against the law. The は marks the thing being discussed; 違法だ is the plain form.
JA: この場所でたばこを吸うのは違法です。
EN: Smoking in this place is illegal.

もちろんそれは違法です

Of course, that's illegal.

— お嬢さん (2016)

その行為はここでは違法です

That act is illegal here.

ここに車を停めるは違法です

It is illegal to park here.

著者許可なしに本をコピーすることは違法です

Copying a book without the author's permission is illegal.

あそこに駐車するのは違法です

It’s illegal to park there.