Mike Scott, the former London Welsh team manager, falsified documents in an effort to cover up the fact he had not secured the correct visa for New Zealand-born scrum-half Tyson Keats.
Copsey maintains the decision to punish the club was unfair, claiming the players and supporters have been left to pay the price for the criminal actions of one man.
According to Premiership Rugby regulations, the decision is final and binding, but London Welsh are exploring all their options.
Asked whether CAS was a possibility, Copsey said: "We are still considering our position and I won't say never.
"I think we need to take stock and not discount anything. (That decision) will be made in a couple of days.
"We don't think the punishment meets the crime. Everything in the original action from the RFU was, in my view, about misconduct. If they had a misconduct charge against the club that is what they should have done. The club has been cleared of any of that sort of doing.
"I think a no points (deduction) situation is fair and proper."
The punishment plunged London Welsh to the bottom of the Aviva Premiership and they are now five points adrift of Sale Sharks with just four league matches remaining.
Copsey accepts the Exiles need to win at least two of their remaining four fixtures to stand any chance of survival but the decision on further action will not be influenced by results.
"The key driver all along is about justice. It is about what we think is the right decision," Copsey said.
"In the same way as the club felt the decision not to allow us into the Premiership last season was unfair and unjust, it fought the case. The club has fought this case so far and it is now whether there is any more mileage in it."
- Sports & Recreation