The phrase "a complex matter that" is correct and usable in written English.
It can be used when discussing a topic or issue that has multiple layers or intricacies that require careful consideration.
Example: "The negotiations surrounding the treaty are a complex matter that requires input from various stakeholders."
Alternatives: "a complicated issue that" or "a multifaceted topic that".
This is a complex matter that doesn't have a clear-cut answer yet, but 2014 could prove to be a perfect storm in how we as a nation approach this issue.
Setting the age for the acquisition of rights is, as described by UNICEF, a complex matter that must "balance the concept of the child as a subject of rights whose evolving capacities must be respected with the concept of the State's obligation to provide special protection".
But Mr. Graham stressed it was a "complex matter" that was best left to the commission to sort out.
This is an important study of the benefits and difficulties of a complex matter that could yield dividends to the two economies and help stabilize the security and well-being of the rest of the world.
Again, this is a complex matter that requires consultation with an experienced professional.
After previous efforts, university officials cautioned that divestment is a complex matter that should be pursued rarely and only when the U.S. government deems that a foreign regime is committing genocide. .
Statehood is a highly complex matter that is not necessarily resolved by a U.N. General Assembly vote.
Driver behaviour is a very complex matter that is influenced by one's knowledge, abilities, and skills on the one hand and personality traits (such as volition, values, and motives) on the other.
But whether or not they are authors is a much more complex matter that merits their attention before, rather than after, they run into trouble at the keyboard.
This is a serious and complex matter that has caused communities to irrupt on both sides.
"I believe that a solution for protecting society is a complex matter, and that the death penalty serves as one of its solutions, but think that alternatives should be pursued on an ongoing basis".
