never read textbook or memoirs of LKY.... 
apparently he quit the labour front after coming back from england
without achieving independence in talks. he would not accept
anything less than that, but the british were only willing to grant
self-government status.
he said he would quit the party and resign as chief minister if he
failed to secure independence, and had to honour his word. he then
verbally challenged lee kuan yew to leave his tg pagar seat (as
leader of opposition then and who had openly opposed his rhetoric
tactics during the talks and for not being contented with
three-quarters independence and coming back with nothing) and he
leave his cairnhill seat, and fight it out in a by-election.
lee kuan yew agreed to it, to david's surprise cos he had not
thought out his tactics properly then and whether he had the
mandate and confidence to win it. david then announced he would
quit parliament for good, but actually founded the workers' party
before the 1959 elections.
the cairnhill seat he vacated was worn by liberal socialist party,
and lee kuan yew won his seat on a stronger margin of 68.13%.
lim yew hock from labour front took over as chief minister, were
tough and arrested many communists, and a multi-party went to
england and got their approval for self-governance, with joining
malaysia as the eventual goal.
david marshall contested and lost in the 1959 elections, but gained
his anson by-election seat (vacated cos the MP passed away) on the
WP ticket in 1961 apparently with some leftist support. the
communists in PAP wanted to show the non-communist in PAP the type
of support they could muster, and this prompted lee kuan yew to
table the famous motion to seperate the communist from the
non-communist in the PAP. they were able to get the half plus one
majority in the parliament, and the rest walked over to the other
side and banded themselves as the Barisan Sosialis.
* i'm writing from memory, u wan to know the whole thing go read
the memoirs of LKY, first book.
quoting from http://en.wikipedia.org/wiki/David_Saul_Marshall,
"Marshall stayed on the backbench, before quitting the ruling
Labour Front party in 1957 and founding the Workers' Party of
Singapore. He lost in the 1959 general election, but was able to
win a by-election in Anson in 1961. After losing his seat again in
1963, he returned to practise law but remained active in opposition
politics until 1972, when J. B. Jeyaretnam became leader of the
Workers' Party.
From 1978 to 1993, Marshall served as Singapore's Ambassador to
France, Portugal and Switzerland. As Singapore's ambassador,
Marshall always defended his country's interests, despite his
differences with Lee Kuan Yew's government. He retired from the
diplomatic corps in 1993.
He died in 1995 as a result of lung cancer."
