The Fife-born, Edinburgh-based crime writer feels his own son, Kit, has been “forgotten” as vaccines were delivered to care homes.
The 26-year-old, who has severe learning difficulties, lives in an Edinburgh care facility, but did not qualify in the first priority group.
People with a “severe or profound” learning disability are in priority group six for the vaccine – but Rankin believes those in Kit's circumstance “should have been prioritised”.
Speaking to BBC Radio Scotland's Drivetime programme, the Inspector Rebus writer said: “Our son can't look after himself and he's in the same group as us – his parents who are healthy 65-year-olds. People with learning difficulties should have been prioritised.
"It's a bit late now. My son will get the jab in the next month or so. But we should learn lessons for the future about what seems to be a bit of a lottery."
Rankin believes there should have been better communication with families throughout the entire programme.
He told the BBC: "The families and the carers have been kept out the loop.
“Life's hard enough for them. This year has been tough without any of the usual services, treatment, education they usually get.
“The idea they're just being forgotten about sitting in isolating in their care homes.
“Both governments keep telling us it's wonderful they've got all the care homes done. No, you haven't. You've got care homes for the elderly done. There's more care homes than that out there.”
Rankin also spoke of his frustration over how Kit's residence was classified as a care home during lockdown – but not for the vaccine programme.
“The disabled don't have a voice," he said. "They've never had a voice and laterally we're starting to hear their representatives, their family and friends, yelling.”
In a recent interview with Times Radio, Rankin highlighted the difficulties faced by families with vulnerable relatives, describing the “tough” situation of being unable to touch or hug his disabled son for almost a year due to the coronavirus pandemic.
“We’ve seen images on TV and we’ve heard from people about the problems they have visiting elderly relatives, but there are lots of us out there that have less elderly relatives who are also in full-time care and it’s tough on these families as well,” he said.
“My son Kit doesn’t really know what the situation is. Luckily he’s surrounded by staff who are looking after him 24/7 and making sure he has a pretty full life.
“But the families haven’t been allowed to visit much.
“In general we see him through a gate, we see him over the wall, there’s no touching, there’s no hugs.”
Rankin said Kit’s carers offered contact with him through Zoom, but due to his visual impairment that is not practical.
“He doesn’t really understand screens or things in two dimensions like picture books and suchlike,” he said.
“He could hear our voices but then he was just confused because then where were we? Why were we not giving him a hug sitting next to him?
“It was working for some of the people in his facility but it wasn’t really helpful for him.”