I asked compliance:
How does ICANN Contractual Compliance use WHOIS data? For example, in the case of a WHOIS inaccuracy complaint, can ICANN Contractual Compliance retrieve data from escrow, or does ICANN Contractual Compliance typically ask the registrar or the registry operator?
And they replied:
ICANN Contractual Compliance uses WHOIS data to review WHOIS Inaccuracy complaints and other complaints related to domain management (e.g., Transfers, Unauthorized Transfer, Domain Deletion, Renewals, etc.). Depending on the nature of the complaint, ICANN Contractual Compliance may ask the registrar for relevant data to investigate the complaint. Compliance may also look at the Registry public WHOIS to supplement its review or processing. Compliance does not use escrowed data for complaint processing as it is not one of the conditions for escrow deposits release under the data escrow agreements and ICANN agreements.
This response has also been posted on the Q & A section of the wiki: https://community.icann.org/x/ahppBQ.
Best regards,
Marika