As Sydney legal eagles polish Westpac's defence against a civil claim by ASIC in the Federal Court for alleged breaches of responsible lending laws, the bank continues to tweak its loan assessment policies.In notifications sent to aggregators this week, Westpac revealed that it has closed another potential gap in its loan serviceability test, which relates to the treatment of unconventional consumer loans marketed by providers such as AfterPay and ZipPay.It appears that loan servicing commitments to these lenders have not always been accounted for by the bank, with brokers not required - until now - to ask loan applicants whether they had to service such debts."Assessing serviceability policy has been updated to include capture of short term buy now - pay later loans used by customers to make a purchase of goods or services," Westpac's mortgage broking unit stated in the notification.This amendment is the latest in a string of announcements this year from the bank after it and other lenders came under pressure from regulators to tighten loan assessment standards.In August, Westpac overhauled its income verification policy for home loan applicants, which exposed the reported income of loan applicants to greater scrutiny.Brokers were instructed to exclude income bonuses from annualised earnings of some homebuyers seeking loan approvals.The bank also cracked down on the inclusion of some social security benefits in a prospective borrower's assessable income.Moreover, brokers were told not to use the current income of a loan applicant employed by a family member in cases where gross earnings had risen sharply in the last year.Whether Westpac's serviceability tests were especially lax in recent years is set to be determined next year when the Federal Court hears ASIC's claims that the bank failed to properly screen borrowers before they signed loan contracts.ASIC alleges that in the three and a half years to the end of March 2015, Westpac used a benchmark instead of the actual expenses declared by borrowers to assess their ability to repay loans.The regulator also claims that the bank failed to have regard for the higher repayments at the end of the interest-only periods when it assessed the ability of loan applicants to make repayments.Westpac is defending the claims, brought under the responsible lending provisions of the National Credit Act.