The Workers' Party (WP) town councillors involved in multimillion-dollar lawsuits over alleged improper payments have raised about $900,000 to fund their legal fees, after launching an online crowdsourcing appeal on Wednesday.

As at 10pm yesterday, WP chairman Sylvia Lim, secretary-general Pritam Singh and former chief Low Thia Khiang collected a total of $907,918 from 5,241 donors, they said in an update on their blog In Good Faith. The trio had collected $477,653 from 2,832 donors at 10pm on Thursday.

The trio first sought the public's help on Wednesday evening, saying they have spent close to $600,000 so far on the legal battle, using their savings and contributions from friends.

This has "depleted our personal resources", they said. "We need financial resources to fight the legal battle and to deal with the prospect of being made a bankrupt."

Within a few hours of the appeal going online on Wednesday night, at least $65,000 was raised.

The MPs sought public contributions via bank transfer, cheque and to Ms Lim's PayNow account. They also asked donors to include an e-mail address, so they could thank them.

In a post on WP's Facebook page yesterday morning, the party clarified that the three MPs are undertaking a private fund-raising effort and it is not raising funds for them.

WP said it has "nothing to do with that effort" and urged the public to be wary of donating money to anyone claiming to represent the party.

The post said: "We also urge supporters not to use the Workers' Party logo or make any claims to represent the party in their personal efforts to promote the private fund raising."

Singapore Management University law don Eugene Tan said it would be "quite a stretch" for the trio's fund-raising efforts to be governed by the Political Donations Act, given that the fund-raising is not for an ostensible political purpose.

They are being sued in their capacity as town councillors and not MPs, he said. "The three WP MPs have been fairly careful in characterising this effort as contributions to a personal matter, notwithstanding the significant political dimension of the case."

The Act covers political associations and candidates, and lists the rules for making and accepting donations, among other criteria.

However, Prof Tan said Mr Low, Mr Singh and Ms Lim have to ensure that the funds collected are used strictly for the lawsuits.

What they do with the excess funds, if any, after the case has concluded is also crucial, he said.

"The excess money will have to be returned to the donors. The funds cannot be channelled to WP or be used for their political purposes unless donors agree to the conversion of use," he added.

The trio and two other town councillors are facing two suits over $33.7 million in alleged improper payments - one brought by Aljunied-Hougang Town Council as directed by an independent panel and the other by Pasir Ris-Punggol Town Council.

The suits claim that the quintet breached their fiduciary duties and have to repay the improper payments made.

They are represented by Senior Counsel Chelva Rajah from Tan, Rajah & Cheah in the case now before the High Court.

The trial, which began on Oct 5, is scheduled to run until Friday.