On the Cup Final being debated in Parliament, I can find no record in Hansard. However, what your Dad most probably means is the article in The Spectator by one J.P.W. Mallalieu, MP for Huddersfield:
'Before the match Arsenal knew that the man they must watch most closely was Liddell, Liverpool and Scotland's flyer. If he got loose, anything might happen. He must not get loose. I remember how, years ago, one tough but not particularly skilful Oxford wing faced a much more skilful but rather less tough wing from Cambridge. In the first minute, acting on instructions, the Oxford man tackled his opponent so hard that both finished in the straw. Even fiercer than the tackle was the glare that accompanied it. Thereafter the glare was enough. No further tackles were needed. I consider such tactics fair.
But on Saturday I saw tactics which were unfair. The first time Liddell got the ball an Arsenal defender's foot got the man, not the ball. Free kick to Liverpool. The next time he got the ball he was tripped. Free kick to Liverpool. The next time he got the ball his face collided with an Arsenal fist. The referee missed this one. So it went on while Liddell, and Liverpool, persistently tried to play football.' In' terms of football morality I am no better than I should be. The best I can say for myself is that I set my face steadfastly against fouling by my own team except where it is absolutely necessary and that I set my face against fouling by my opponents except in my own penalty area when the referee is watching. But I don't like fouling by any team in Cup Finals and, thank goodness, very seldom see it.
Were the winners once again " Lucky " Arsenal? No. Just slightly dirty.'
http://archive.spectator.co.uk/article/5th-may-1950/10/cup-final
The 'debate' continued in the Spectator for some weeks afterwards, with Northerners backing up Mallalieu's words and Southerners pouring scorn on them.
Liddell of course, being a Gentleman, didn't get involved and never - certainly publicly - accused the Arsenal of dirty tactics at that Cup Final.
Interesting. I always thought there was no truth in it whatsoever but there'd be a lot more 'Chinese Whispers' in those days and I can see how the rumour came about. It'd be interesting to know from any arl Scousers on here whether somebody got called a 'Forbes' or if it was a 'Compton', after backing down from a fight.
On the 10,000 ticket allocation, I might have this slightly wrong as it's based on my memory, of my Dad's memory but in those days nobody was expecting anywhere near 10,000 to travel down to Wembley but Liverpool was well over subscribed. They ended up doing a ballot where you sent a stamped addressed envelope to the ticket office. The lucky ones who were picked out had a ticket office stamp on them and returned to the address. You then took the envelope back to the ticket office again to get your ticket.
The anger over this match lasted a long, long time and still gets mentioned by the arl ones.
For me though it was the 87 Littlewoods Cup Final.