How might legislation that appears contrary to the rule of statute be challenge lower than the Human Rights Act 1998?

I have to answer this question for my regulation exam and I have absolutely no impression about what to write. I've checked on the internet and in books but I can't find anything at adjectives. I would appreciate any help at all.
What sort of legislation might appear contrary to the rule of decree?

Maybe something that deprives people of the right to a fair trial? That could be challenge under article 6.

Maybe something that allowed punishment for something that wasn't illegal when it be done? That could be challenged under article 7.

Related Questions: