With advances in DNA detection, we in the UK have had a number of previously unsolved cases brought to trial and succesfully prosecuted.
The most recent one I can think of is here,
http://news.bbc.co.uk/1/hi/england/london/3122841.stm
Now this particular brute committed his offence when young and is still at early middle age, but there have been others where the criminal was considerably older at the time of the offence, and with the intervening years are now approaching elderly.
We still chase down (rather halfheartedly) the occasional former Nazi etc nearly 60 years after their crimes.
The victims of many of these crimes, such as rape and murder, and the close family members of those victims may well endure a lifetime of torment.
I find it hard to show much compassion for elderly criminals based solely on age or the time related remoteness of their crimes.
The only possible consideration that might be given is the charactor of the criminal in the intervening years, but even that would have to be of secondary importance to victim impact.
Let’s look at this wonderful example of humanity.
http://news.bbc.co.uk/1/hi/northern_ireland/3130149.stm
This chap kept actual murders at arms length by plotting and getting others to carry out his directions.
The case set a precedent in Eire for many reasons, but one significant one was that it showed that those who commission such crimes can be brought to trial just as if they had done it themselves.
The idea is that if you are the proven leader of an organisation whose stated policy is to murder, then you are responsible in part for those crimes.
The man is 53 years old, it is widely known (there is evidence BTW) that he was responsible for the planning of the Omagh bombing in 1998.
Now he is serving a 20 year sentence, that is not far off an entire life sentence for a 53 year old , his case is a good one to look at in this context because it is so borderline, do you think that maybe he should have been awarded say 15 years because of his age ?