Fair enough, I stand corrected. Clearly 70% of the population is wrong, it's probably a good job that democracy doesn't always work
There looks to be a bit of statistical jiggery-pokery going on to get a desired headline - look at who commissioned the survey, and for what program it was to be used in.
If you look at the tables of data (not the "headline"), only two offences actually registered above 50%; adult murder (51%) and child murder (62%). So whilst they can claim 70%, it would appear that there is not a consensus on what offences should carry it as the ultimate sanction.
The actual question asked is interesting as well (their capitals, not mine): "IN YOUR OPINION, WHICH OF THE FOLLOWING CRIMES, IF ANY, DO YOU THINK THE UK SHOULD STILL HAVE THE DEATH PENALTY FOR AS THE MAXIMUM POSSIBLE PENALTY?"
. Normally if I ask a question of the form, "should we still have this", it's about something we already have, and I'm asking whether we should maintain it, not should we start (or re-start) doing it.
Build it like you owned it!