Voice based access control with increased assurance

A method of access control includes receiving an access request transaction from one of a first identity sensor. Current confidence information is determined for the access request transaction. Prior confidence information is determined for at least one prior access request transaction associated with the user from at least one second identity sensor. A total confidence score value is generated based on a confidence function applied to the current confidence information and the prior confidence information. The total confidence score value is compared with a confidence threshold value for the secure resource associated with the access request transaction. Access to the secure resource is granted, in response to determining that the total confidence score value meets the confidence threshold value. The access to the secure resource is denied, in response to determining that the total confidence score value does not meet the confidence threshold value.