Afterall, they basically had him appearing in a new film without his consent and if you have seen Rogue One: A Star Wars Story you know we are not talking about some minor cameo here. He was a significant part of the supporting cast and, having died in 1994, was unable to give his permission, sign a contract, be paid for the role, or indeed have any say in how he appeared at all. Legally speaking, Walt Disney Pictures and Lucasfilm crossed no lines. They had permission from Peter Cushing's estate to use his image and the dead basically have no rights anyway, but that hasn't stopped some fans from saying that it is simply unethical.
This is not the first time we have seen controversy like this. When Audrey Hepburn was recreated to advertise Galaxy chocolate bars a few years ago, half the world was impressed with the admittedly incredible CGI, while the other half was appalled that the 1950s icon was being used to sell confectionery. Again, Hepburn's estate – her two sons Sean Ferrer and Luca Dotti – had given their permission for her image to be used and received a fee for their trouble.
Even before then, Fred Astaire danced with the Dirt Devil vacuum cleaner a decade after his death thanks to his widow giving her permission, but his daughter said she was "saddened that after his wonderful career he was sold to the devil". The list goes on, and as technology only becomes more able to convincingly bring back long since lost stars, it will only be getting longer.
Admittedly, there is a big difference between a former actor's image being used to sell something (which in all possibility they would never have agreed to) and them reprising a role they were happy to sign on for when they had been alive. When Paul Walker tragically died halfway through shooting Furious 7 (2015), no one blinked an eye when Universal Pictures used his brothers and digital effects to complete his role. Walker had obviously already given his consent to appear in the movie so it wasn't much of stretch to say that he would have wanted it completed, digitally enhanced or otherwise.
Given that there is 39 years between Star Wars: Episode IV - A New Hope (1977), which saw Peter Cushing first take on the iconic role of Tarkin, and his digital recreation in Rogue One: A Star Wars Story, it is a little harder to say for sure that he would have absolutely agreed to it. However, Rogue One's visual effects supervisor John Knoll feels confident that it would have been the case. "We weren't doing anything that I think Peter Cushing would've objected to." He told The Guardian. "I think this work was done with a great deal of affection and care. We know that Peter Cushing was very proud of his involvement in Star Wars and had said as much, and that he regretted that he never got a chance to be in another Star Wars film because George [Lucas] had killed off his character." He added that "it was done in consultation and cooperation with his estate. So we wouldn't do this if the estate had objected or didn't feel comfortable with this idea."
It is a discussion that has gained more attention in light of Carrier Fisher's recent death, who also appeared in digital form in Rogue One. In Fisher's case, she gave permission for the effects team to recreate her younger self for a Princess Leia cameo while she was still alive. When news of her sudden and tragic death on 27 December 2016 (a fortnight after the film was released) spread, it was naturally assumed by most that the same computer generated trickery would be used to complete her role in Star Wars: Episode VIII and Star Wars: Episode IX. In fact, some outlets reported that representatives had spared no time in negotiating with her estate for the rights to do so.
Since then, Walt Disney Pictures and Lucasfilm have confirmed that they will not be using digital effects to recreate Carrie Fisher for either of the sequels, stating on the official Star Wars website: "We want to assure our fans that Lucasfilm has no plans to digitally recreate Carrie Fisher's performance as Princess or General Leia Organa." Is this because they couldn't get the rights from her estate to do so? We just don't know. Lucasfilm president Kathleen Kennedy revealed to Knoll that Fisher approved of her part in Rogue One ("Kathy [Kennedy] called me right after she showed it to [Fisher] and said how fantastic she thought it was. So she was very much in favour of it."), so it is perfectly feasible that it is actually because her role in Star Wars: Episode VIII already reaches some kind of conclusion.
No matter what, the question still remains whether it is ethical to profit from a dead actor's digital resurrection. After all, despite the joy movies bring us, they are still made to make money and it seems no-one (Disney included) minds who they have to bring back to do so. Ultimately, I think it is safe to say that Peter Cushing would have wanted to have been a part of Rogue One: A Star Wars Story. Maybe he would have played the role differently... maybe he would have had suggestions for director Gareth Edwards... we will never know. But fans were certainly pleased to see the iconic villain back on the big screen again, and as long as his family were happy with him reprising his role, who are we to say otherwise?